Note: Descriptions are shown in the official language in which they were submitted.
CA 02370897 2002-02-08
Helicopter Line Wear Cover
FIELD OF THE INVENTION
The present invention relates generally to helicopter line wear covers and
more specifically to
helicopter line wear covers protecting a load bearing line and a non-load
bearing line and
preventing tensile forces from causing wear on the lines.
BACKGROUND OF THE INVENTION
Helicopters are commonly employed in lifting, transporting and unloading of
various cargo items
suspended from a line or cable attached to the helicopter at one end and to
the load to be lifted at
the other. Helicopter load lines are usually comprised of two separate lines
or cables, a load
bearing line which supports the load and connects it to the helicopter, and a
control line used to
send control signals to the load latch permitting the helicopter operator,
sitting in the helicopter
cockpit, to :remotely unlatch a load release mechanism to release the load
while the helicopter
remains in the air:
In the past, helicopter load lines made of steel wire rope were employed as
the load bearing line.
However, wire ropes are heavy and, as helicopters have limited lifting
capacity, heavy wire ropes
meant reduced loads could be carned by the helicopter. As a consequence,
synthetic ropes have
recently come into favour to replace wire ropes: Synthetic ropes have the
advantage of being
considerably lighter than wire ropes with equal carrying capacity, permitting
heavier loads to be
carried by the helicopter with a synthetic rope as compared to a wire rope: As
a consequence,
synthetic ropes have successfully replaced wire ropes in most helicopter load
lifting operations
employing a helicopter load line.
Synthetic ropes suffer from the disadvantage that they are much more prone to
wear when
contacted by other objects, such as the non-load bearing control wire
positioned adjacent the load
bearing line, as well as foreign objects on the ground, such as trees and the
like which contact the
synthetic load bearing line when the line is lowered to pick up a load, or to
drop off a load. This
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is a particularly difficult problem in helicopter logging operations where
helicopters are used to
carry logs from a logging site to a collection site for transport to a lumber
mill. The line often
contacts trees and other foreign objects in raising and lowering a load for
transport or to be
dropped.
In order to protect synthetic load bearing lines from physical damage, covers
have been
employed to cover all, or a part of, the load bearing line preventing the line
from contacting
foreign objects thereby reducing the wear and tear on the line, lengthening
its life and reducing
the possibility of line breakage. These covers usually also cover the control
line to protect it
from damage and wear from the elements and from foreign matter, such as tree
branches and the
like.
When a cover is wrapped about the control line and the load line, both lines
can be damaged
when they rub together, due primarily to vibrational forces on the lines which
causes wear on
both lines as they contact one another. A cover maintains the load bearing
line and control line
in close proximity arong all, or substantially all of, the length of each of
these lines. This can
lead to premature wear and breakage of the load bearing line as well as the
control line due to
frictional forces when they rub together.
As a consequence, there is a need for a helicopter line wear cover which is
cheap to manufacture,
simple to install which protects both the control line and load line from the
elements and foreign
material and which separates and protects the two lines from each other
thereby avoiding wear
on both lines.
SUMMARY OF THE INVENTION
A cover for protecting and separating a load bearing cable used for the
lifting of a load
suspended from a helicopter from a non-load bearing cable used for controlling
the release of the
load, includes a pair of elongated flat side members having first and second
longitudinal edges,
the members connected together along two lines of attachment longitudinally to
form a first tube
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between the side members. A first attachment member.is attached to one of the
side members
adjacent the first edge and a second attachment member is attached to the
other of the side
members remote from the first edge. When a first and second attachment members
are attached
together, the side members form a second tube, parallel, with the first tube,
and separated from
the first tube by one of the side members. The diameters of the first and
second tubes are large
enough .to enable free longitudinal movement of each of the cables within
respective first and
second tubes when the first and second attachment members are attached
together.
In a further embodiment of the invention; a cover for protecting and
separating a load bearing
cable used for the lifting of a load suspended from a helicopter from a non-
bearing cable used for
controlling the release of the load includes' an elongated cover member having
first and second
longitudinal edges, a first tube connected longitudinally to one side of the
cover member, a first
attachment member attached to onside of the cover member adjacent the first
edge and a second
attachment member attached to the other side of the covei member adjacent the
second edge: A
connecting member connects the first end of the load bearing cable connected
to the helicopter to
the cover to support the cover relative to the first end. When the first and
second attachment
members are attached together, the cover member forms a second tube parallel
with the first tube
and the diameters bf the first and second tubes are large enough to enable
free longitudinal
movement of each of the cables with respective first and second tubes when the
first and second
attachment members are attached together.
In a further embodiment, a first securing element attaches the first
attachment member and the
side members together and a second securing element attaches the second
attachment member
and the side members together wherein the first and second securing elements
define the first
tube between the side members.
In a further embodiment, the first securing element attaches a first edge of
the first attachment
member to a first edge of the side members and the second securing element
attaches a first edge
of the second attachment member to the second edge of the side member with a
third securing
element attaching a second edge of the first attachment member to one of. the
lines of attachment
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and a fourth securing element attaching a second edge of the second attachment
member to the
other of the lines of attachment.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a perspective view of the helicopter line wear cover and top
attachment member of
the present invention.
Figure 2 is a cross-sectional view taken at line 2-2 of Figure 1.
Figure 3 is a top plan view of the helicopter line wear cover of Figure 1 laid
flat.
Figure 4 is a cross-sectional view taken along line 4-4 of Figure 3.
Figure 5 is a cross-sectional view of the top attachment member taken along
line 5-5 of Figure 1.
Figure 6 is a top plan view of the top attachment member of the subject
invention, laid flat.
Figure 7 is a bottom plan view of the top attachment member of Figure 6.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Figure 1 depicts helicopter line cover 10 made up of elongated line cover 12
and top attachment
member 14. Cover 12 is depicted encircling load line 16 which is a load
bearing line attached to
a load at its lower end (not shown) and attached to loop eye 18 at its upper
end. Cover 12 also
encircles control line 20 used to control release of the load which is
attached at its lower end to
the load release mechanism (not shown) for attaching the load to the load line
16 and at its upper
end to a control system (not shown) accessible in the helicopter cockpit to
enable manual release
of the load from the helicopter on remote actuation of the release mechanism
load through
control line 20.
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Referring to Figures 3 and 4, cover 12 is depicted in its open position, laid
flat. Cover 12 is
made up of upper side member 22 and lower side member 24 with member 22
overlying member
24. Cover 12 further includes loop fastener 26 comprising a first attachment
member of a loop
and hook fastening system attached to upper side member 22. Cover 12 further
includes hook
fastener 28 comprising a second attachment member; of a loop and hook
fastening system
attached to lower side member 24.
Loop fastener 26 is attached to cover 12 by means of outer sewn thread 30
adjacent first edge 32.
Thread 30 extends through both upper side member 22 and lower side member 24
to attach loop
fastener 26 and upper side member 22 and lower side member 24 together
adjacent edge 32.
Similarly, loop fastener 26 is attached to cover 12 by means of inner sewn
thread 34 which
extends through loop fastener 26, upper side member 22 and lower side member
24 to attach
fastener 26 and members 22, 24 together at inner sewn thread 34. ;
Hook fastener 28 is attached to lower side member 24 adjacent edge 36 which is
opposite to edge
32. Cover 12 extends longitudinally for a substantial length, substantially
equal to the length of
line 16 and 20.
Outer sewn thread 38 attaches hook fastener 28 to lower side member 24
adjacent edge 36 and
also attached hook fastener 28 and upper and lower side members 22 and 24
together. Inner
sewn thread 40 attaches the inner edge 42 of hook fastener 28 to lower side
membei 24 and also
attached hook fastener 28 arid upper and lower side members 22 and 24
together. Referring to
figure 4, side members 22, 24 may be attached together at each end 66, 68 of
hook fastener 28
and each end 70, 72 of loop fastener 26.
As best seen in Figure 4, the segment of upper side member 22 and lower side
member 24
between threads 34 and 40 and that portion of ends 62; 64 between threads 34
and 40, are not
fastened together. Threads 34 and 40 thereby form a first tube 42
longitudinally between
members.22 and 24 and threads 34 and 40.
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It can also be seen that loop fastener 26 is substantially wider than hook
fastener 28; in order to
provide adjustability when cover 12 is wrapped around line 16 and to permit
attachment of top
attachment member 14, as is discussed below.
Referring to Figure 2, cover 12 is depicted surrounding lines 16 and 20 as
shown along line 2-2
of Figure 1. Cover.12 is looped in a circle with hook fastener 28 attached to
loop fastener 26 to
form a releasable attachment with cover 12 encircling lines 16 and 2f. When in
this position,
lower side member 24 forms a second tube 44 which encircles line 16. Figure 2
depicts control
line 20 extending through first tube 42 and load line 16 extending through
second tube 44. It can
be seen that tube 42 is dimensioned large enough in diameter to permit line 20
to extend loosely
within tube 42. As well, the user will select the appropriate position for
attachment of loop
fastener 26 to hook fastener 28 to provide loose fitting enclosure of load
line 16 within second
tube 44. 'This permits lines 16 and 20 to move longitudinally within tubes 42
and 44 while
minimising the frictional forces on member 22 and 24 as lines 16 and 20 expand
and contract
within tubes 42 and 44. It can also be seen that member 24 separates line 16
from line 20
preventing frictional contact between lines 16 arid 20 thereby minimizing
frictional damage to
those lines as they vibrate within tubes 42 and 44.
Due to the fact that tubes 42 and 44 are loosely fit about liens 20 and 16
respectively, cover 12
must be supported at its upper end to prevent cover 12 from sliding downwardly
through force of
gravity impairing the ability of cover 12 to protect lines 16 and 20 and
otherwise interfering with
the lifting and release of the load.
Top attachment inembei 14 is designed to support cover 12 when wrapped around
lines 16 and
20 to prevent cover l2 from moving downwardly along lines 16 and 20 when in
use. Referring
to: Figures 5, 6 and 7, top attachment member 14 is generally hourglass-shaped
with wider
portion 46 connected to narrower portion 48 be means of intermediate portion
50. Referring .
briefly to Figure 1, intermediate portion 50 is narrow in width to enable
portion 50 to extend
through Loop 18 to support portions 46 and 48.
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Referring back to Figure 7 which depicts inner side 58 of member 14, wider
portion 46 includes
a pair of longitudinal spaced parallel loop portions 52 of a loop and hook
fastening system along
outer edges of wider portion 46. Narrower portion 48 includes a pair of
longitudinally hook
portions 54 of a loop and hook fastening system along outer edges of narrower
portion 48.
As depicted in Figure 6; outer side 60 of member 14 includes a pair of
elongated loop portions
56 of a loop and hook fastening system attached along outer edges of wider
portion 46.
As can be seen best in Figure 5, when member 14 is attached to line cover l2
with portion 50
through eye 18 as depicted in Figure 1, wider portion 46 extends substantially
about cover 12.
When intermediate portion 50 extends through loop eye 18, wider portion 46,
and narrower
portion 48 extend downwardly from loop eye 18. Wider portion 46 is positioned
with hook
portions 52 on the inner side 58 of member 14. Both of the parallel hook
portions 52 are then
attached to loop fastener 26 of cover 12. This rigidly attaches member 14 to
cover 12 with loop
portions 56 facing outwardly in parallel alignment adjacent one another.
Hook portion 54 attached to narrower portion 48 on the upper side 58 of member
14 may then be
attached to loop portion 56 to secure wider portion 46 to narrower portion 48
thereby securing
member 14 through loop. eye 18 further securing member 14 and cover 12 to loop
eye ,18 at the
upper portion of load line l6.
Users simply thread control line 20 through first tube 42 along substantially
the entire length of
control line 20. Cover 12 is then wrapped loosely about load line 16 and
attached by means of
fasteners 26 and 28, as depicted in Figure 2. Attachment member 14 is then
extended through
loop eye 18, preferably by threading narrower portion 48 through eye 18 so
that intermediate
portion 50 is positioned within eye 18. Wider portion 46 and narrower portion
48 are then '
positioned downwardly and member 14 is attached to cover 12 by means of hook
portion 52
attached to loop fastener 26. Narrow portion 48 is then attached to wider
portion 50 by
connecting hook portions 54 to loop portions 56.
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It will be readily appreciated that other means for attaching the various
members can be
employed, in addition to a loop and hook fastening system including a zipper
system, hook and
eye system, and other suitable means to releasably secure top attachment
member 14 to line
cover 12 and to attach cover 12 and member 14 to loop eye 18. It should also
be appreciated that
loop and hook fastening components of a loop and hook fastening system may be
reversed from
that as described herein without departing from the invention.
HBR/982252
