Note: Descriptions are shown in the official language in which they were submitted.
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HELICOPTER-BORNE POWER LINE DEICER
Technical Field
[0001] A helicopter-transportable and controllable high voltage
electric power transmission line deicer having a vibrator to dislodge
snow and ice from the power line while the deicer is rollably positioned
on the power line.
Back rg ound
[0002] High voltage electric power transmission lines located in
regions prone to blizzards, freezing rain, etc. can accumulate significant
snow or ice loads. If the weight of the accumulated snow or ice be-
comes excessive the power line may be damaged. For example, the
weighted power line may sag and contact a tree or other object, result-
ing in a short circuit and disrupting the power line's electric power
transmission capability. The weighted power line may also break away
from its support structure, or the line itself may break if it is incapable
of supporting the weight of the accumulated snow or ice-again disrupt-
ing the power line's electric power transmission capability. In an
extreme case, the weight of an ice or snow-bearing power line may
damage the power line's support structure. Electric power transmission
lines located in such regions are accordingly inspected regularly to
detect snow or ice accumulation. Efforts are made to dislodge snow and
ice from such lines before the accumulating snow and ice can disrupt the
power line's electric power transmission capability. The power line
deicer described below assists such efforts.
Brief Description of Drawings
[0003] Exemplary embodiments are illustrated in referenced
figures of the drawings. The embodiments and figures disclosed herein
are to be considered illustrative rather than restrictive.
[0004] Fig. 1 is a front elevation view of the power line deicer.
[0005] Fig. 2 is a rear elevation view thereof.
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[0006] Fig. 3 is a left side elevation view thereof and schematically
shows three different power line positions to illustrate maneuvering of
the deicer into rollable position on the power line.
[0007] Fig. 4 is a partially sectioned left side elevation view
showing an alternative vibrator arrangement.
[0008] Fig. 5 schematically and pictorially shows a helicopter
towing the deicer along a power line after maneuvering the deicer into
position on the power line. The helicopter and deicer are depicted on an
enlarged scale, relative to the power line and its support structure.
[0009] Fig. 6 is a partially fragmented, partially sectioned front
elevation view, on an enlarged scale, of the vibrator head portion of the
power line deicer.
[0010] Fig. 7 is a partially sectioned left side elevation view of the
vibrator head portion of the power line deicer.
Description
[0011] Throughout the following description specific details are set
forth in order to provide a more thorough understanding to persons
skilled in the art. However, well known elements may not have been
shown or described in detail to avoid unnecessarily obscuring the
disclosure. Accordingly, the description and drawings are to be re-
garded in an illustrative, rather than a restrictive, sense.
[0012] Figs. 1, 2 and 3 depict a power line deicer 10 rollably
positioned atop a high voltage electric power transmission line or cable
12. Deicer 10 incorporates a frame having a pair of spaced vertical
steel members 14, 16 fixed (e.g. welded) between horizontal steel
braces 18, 19, 20, 21. Steel support beam 22 is fixed (e.g. welded)
atop and extends outwardly beyond the opposed ends of vertical mem-
bers 14, 16. Steel platform support frame 23 is fixed (e.g. welded) to
the lower ends of vertical members 14, 16 and extends forwardly and
rearwardly thereof, as best seen in Fig. 3. Steel horizontal platform 24
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is fixed (e.g. welded) within and supported by frame 23. Opposed pairs
of steel forward and rearward bracing struts 26, 28 are fixed (e.g.
welded) between the upper ends of vertical members 14, 16 and the
opposed forward and rearward corners of platform support frame 23.
Steel lateral bracing struts 30, 32 are fixed (e.g. welded) between the
opposed outward ends of support beam 22 and the outward, central, side
portions of vertical members 14, 16 respectively.
[0013] Eye bolts 34, 36 are fastened through and protrude atop
support beam 22, outside vertical members 14, 16 respectively. Shack-
les 38, 40 are coupled to eye bolts 34, 36 respectively. Harness cables
42, 44 are in turn coupled to shackles 38, 40.
[0014] Wheel hubs 46, 48 are rotatably mounted on the opposed
outward ends of the forward side of support beam 22. As best seen in
Fig. 3, hubs 46, 48 are mounted so that their rotational axes R extend
forwardly and downwardly at an acute angle a relative to a notional
plane P substantially parallel to a plane containing vertical members 14,
16 and support beam 22. This assists in maintaining deicer 10 atop
power line 12, and also assists in maintaining vibrational contact with
power line 12, after deicer 10 is positioned atop power line 12 and
operated as explained below.
[0015] Stiff-bristled brush 50 (Fig. 1) is mounted on the same (i.e.
forward) side of support beam 22 as wheel hubs 46, 48 and between
vertical members 14, 16 such that brush 50's bristles will contact power
line 12, after deicer 10 is positioned atop power line 12 as explained
below.
[0016] Optional hoisting bracket 52 can be fixed (e.g. welded)
centrally atop support beam 22 for use in ground-based manipulation
and maintenance of deicer 10.
[0017] A conventional concrete vibrator, such as a one incorporat-
ing an electric motor model no. 1.2 OZ, a shaft part no. FS 07 OZ and
a head part no. H 125 OZ-all available from Oztec Industries, Inc. of
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Port Washington, NY is mounted on deicer 10. Specifically, gasoline
engine powered electric power generator 54 is fastened (e.g. strapped or
bolted) atop platform 24 and electrically connected to air motor 56,
which is mounted in support bracket 58. Support bracket 58 is fastened
(e.g. bolted) to steel mounting plate 60, which is fixed (e.g. welded) in
a lower central region between vertical members 14, 16. Air hose 62 is
coupled between air motor 56 and vibrator head 64. As best seen in
Figs. 6 and 7, vibrator head 64 is mounted on the forward side of
support beam 22, in longitudinal alignment with and spaced forwardly
from the upper forward end of vertical member 14. Clamp 66 is
tightened over the lower end of vibrator head 64 against steel bracket
68, which is fixed (e.g. welded) to the forward side of vertical member
14 and extends transversely to either side thereof. Steel sleeve 70 is
formed at the juncture of vertical member 14 and the leftward (as
viewed in Fig. 1) one of bracing struts 26 to assist in retaining vibrator
head 64 in position on deicer 10. Steel stop flange 72 is fixed (e.g.
welded) atop and projects forwardly of support beam 22, in alignment
with vertical member 14, to limit upward and forward-rearward move-
ment of vibrator head 64. Vibrator head 64 can be biased forwardly to
improve contact with power line 12, for example by welding a suitable
shim to vertical member 14.
[0018] The concrete vibrator's electronic control unit 74 is fas-
tened (e.g. bolted) to mounting plate 60, opposite air motor 56. Control
unit 74 is electrically coupled to air motor 56 and to generator 54. As
illustrated by dashed line 76 (Fig. 1) control unit 74 is also electrically
connected to a remote controller (not shown) located within helicopter
100 (Fig. 5).
[0019] In operation, deicer 10 is suspended beneath helicopter 100
on tether 102, and the tether's lower end is coupled to harness cables
42, 44 as shown in Fig. 5. High voltage electric power transmission
line or cable 12 is commonly supported between a pair of towers 104,
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106 and is typically one of several (e.g. three) substantially parallel
power lines supported at spaced intervals by towers 104, 106. After
detection of snow or ice accumulation on power line 12, a pilot ma-
noeuvres helicopter 100 to position deicer 10 with support beam 22
extending substantially parallel to power line 12 such that power line 12
is approximately in dashed line position "A" (Fig. 3) relative to deicer
10. Then, as indicated by arrows 78 and 80 in Fig. 3, the pilot ma-
noeuvres helicopter 100 to move deicer 10 transversely and downwardly
toward power line 12, until forward struts 26 contact power line 12, as
indicated in Fig. 3 by dashed line position "B". The pilot then contin-
ues to manoeuver helicopter 100 to move deicer 10 further transversely
and downwardly, such that forward struts 26 slide transversely and
downwardly against power line 12 until wheel hubs 46, 48 contact and
are rollably positioned atop power line 12 as seen in Figs. 1, 2 and 3.
[0020] After deicer 10 is rollably positioned atop power line 12,
the pilot (or another person in helicopter 100) actuates control unit 74
via the remote controller electrically coupled thereto to start generator
54, thus supplying electric power to air motor 56 which delivers pres-
surized air through hose 62 to vibrator head 64, causing vibrator head
64 to rapidly vibrate forwardly and rearwardly as indicated by arrows
81 in Fig. 6. As best seen in Figs. 3 and 6, vibrator head 64 contacts
power line 12 when deicer 10 is rollably positioned atop power line 12,
due to the above-described forward and downward extent of the rota-
tional axes R of wheel hubs 46, 48. Vibratory force produced by
vibrator head 64 is accordingly continually applied directly to power
line 12, dislodging accumulated snow and ice from power line 12.
[0021] If the vibratory force is insufficient to dislodge substantially
all snow and ice accumulated along power line 12 between towers 104,
106 the pilot can manouevre helicopter 100 as indicated by arrow 82 in
Figs. 1 and 5 to slowly tow deicer 10 along an upwardly inclined
section of power line 12, or to allow deicer 10 to slowly roll along a
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downwardly inclined section of power line 12. Such towing or rolling is
facilitated by wheel hubs 46, 48 which roll along power line 12 as
deicer 10 moves therealong. As deicer 10 moves along power line 12,
snow and ice contacted by brush 50's bristles is swept off power line
12, complementing the snow and ice dislodgment capability of vibrator
head 64. The portions of wheel hubs 46, 48 which contact power line
12 may be optionally coated with rubber or a similar material to reduce
skidding or slippage of wheel hubs 46, 48 as deicer 10 is towed along
power line 12.
[0022] After deicer 10 has been operated to sufficiently dislodge
accumulated snow and ice from power line 12 between towers 104, 106
the pilot (or another person in helicopter 100) actuates control unit 74,
via the remote controller electrically coupled thereto, to deactivate
generator 54, thus stopping the supply of electric power to air motor 56
and placing vibrator heard 64 in an inactive (i.e. non-vibrating) state.
The pilot then manoeuvres helicopter 100 to move deicer 10 trans-
versely and upwardly away from power line 12. The pilot can then
manouevre helicopter 100 to move deicer 10 to another power line from
which accumulated snow and ice is to be dislodged.
[0023] Fig. 4 is similar to Fig. 3, except that air hose 62 is short-
ened to facilitate vertical positioning of air motor 56 directly beneath
vibrator head 64. This arrangement is somewhat more compact than the
arrangement depicted in Figs. 1, 2 and 3 but may require modification
of air hose 62 if a sufficiently short hose is unavailable as a stock
purchase item for use with air motor 56 and vibrator head 64.
[0024] While a number of exemplary aspects and embodiments
have been discussed above, those of skill in the art will recognize
certain modifications, permutations, additions and sub-combinations
thereof. For example, instead of providing a pair of wheel hubs 46, 48
one may provide a single wheel hub positioned centrally atop support
beam 22.
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[0025] As another example, one may substitute a pair of flanged
rollers for wheel hubs 46, 48 (or a single flanged roller positioned
centrally atop support beam 22). Alternatively, a cushioned, inverted-V
shaped pad could be substituted for wheel hubs 46, 48 or for a roller or
rollers, although such a pad may prevent towing of deicer 10 along
power line 12.
[0026] As a further example, the relatively heavy gasoline engine
powered electric power generator 54 is advantageously mounted on a
lower part of deicer 10's frame (e.g. on platform 24) in order to lower
deicer 10's center of gravity, but such mounting is not essential.
Persons skilled in the art will also understand that an alternative electric
power source such as a battery, fuel cell or inverter could be substituted
for generator 54. Moreover, instead of using an electric power source
such as generator 54, one could use a non-electric power source and a
vibrator which does not require electric power. For example, a me-
chanically actuated vibrator could be mechanically coupled to a gasoline
powered engine.
[0027] As yet another example, generator 54 could be mounted
anywhere on deicer 10's frame although it is preferably mounted low on
the frame to improve in-flight stability and so that generator 54 does not
impede the helicopter's pilot's visibility of wheel hubs 46, 48 during
placement of deicer 10 on power line 12 or while deicer 10 is towed
along power line 12.
[0028] As a still further example, it is not essential that vibrator
head 64 contact power line 12 as previously described, although such
contact is preferred. Adequate dislodgment of snow and ice from power
line 12 can be attained even if vibrator head 64 does not contact power
line 12, since vibratory forces produced by vibrator head 64 cause
deicer 10 to vibrate in its entirety, thus imparting adequate vibrational
forces to power line 12.
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[0029] It is therefore intended that the appended claims and claims
hereafter introduced be interpreted to include all such modifications,
permutations, additions and sub-combinations as are within their true
spirit and scope.
