U.S. patent application number 10/706047 was filed with the patent office on 2004-05-20 for wind mill with a suspension for cables and the like, such suspension for cables and the like and a holder for such suspension.
This patent application is currently assigned to DAN-CONTROL ENGINEERING A/S. Invention is credited to Kirkegaard, Karsten, Kristensen, Per, Lindberg, Peder Wehner.
Application Number | 20040094965 10/706047 |
Document ID | / |
Family ID | 8106995 |
Filed Date | 2004-05-20 |
United States Patent
Application |
20040094965 |
Kind Code |
A1 |
Kirkegaard, Karsten ; et
al. |
May 20, 2004 |
Wind mill with a suspension for cables and the like, such
suspension for cables and the like and a holder for such
suspension
Abstract
A wind turbine has a suspension and holders for such
suspensions. Elongated members such as electrical power cables can
be suspended from the nacelle of a wind turbine and down through
the tower of the wind turbine. The suspension utilizes either a
high friction between an inner rod and outer plates to hold the
member by ensuring that the length of the inner rod and the
supporting plates is at least four times the diameter of the
members or a more mechanical holding of the members by providing
beads in clamping portions constituting the suspension.
Inventors: |
Kirkegaard, Karsten;
(Randers, DK) ; Kristensen, Per; (Randers, DK)
; Lindberg, Peder Wehner; (Grenaa, DK) |
Correspondence
Address: |
BIRCH STEWART KOLASCH & BIRCH
PO BOX 747
FALLS CHURCH
VA
22040-0747
US
|
Assignee: |
DAN-CONTROL ENGINEERING A/S
|
Family ID: |
8106995 |
Appl. No.: |
10/706047 |
Filed: |
November 13, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10706047 |
Nov 13, 2003 |
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09880904 |
Jun 15, 2001 |
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6713891 |
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09880904 |
Jun 15, 2001 |
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PCT/DK99/00708 |
Dec 17, 1999 |
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Current U.S.
Class: |
290/55 |
Current CPC
Class: |
H02G 7/00 20130101; Y02E
10/72 20130101; F03D 80/85 20160501 |
Class at
Publication: |
290/055 |
International
Class: |
F03D 009/00; H02P
009/04 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 17, 1998 |
DK |
PA 1998 01661 |
Claims
1. A wind turbine comprising a stationary part including a tower
(1) extending substantially vertically, a nacelle (2) comprising a
wind rotor having at least one blade arranged on a main shaft
having a substantially horizontal rotation axis and a power
transmission system, a yawing system comprising a stationary part
being fixed to an upper end of the tower (1) and a movable part
being fixed to the nacelle (2), the stationary part and the movable
part being designed so that the nacelle (2) is being supported
vertically and horizontally by the tower (1) and may pivot
relatively to the tower about a substantially vertical yawing axis
(A), and a plurality of elongated members such as bendable
electrical power cables (9) for transferring electrical power from
the generator system, the plurality of elongated members such as
the power cables (9) being fastened at an upper end to the nacelle
(2) and at a lower end to the stationary part of the wind turbine,
and a passage (4) being defined between the nacelle (2) and the
tower (1) and being positioned so that the vertical yawing axis (A)
passes through the passage (4), the plurality of elongated members
such as the electrical power cables (9) passing through the passage
(4), said wind turbine further comprising at least a first
suspension (5) being suspended by the nacelle (2), the first
suspension defining substantially vertically extending supporting
surfaces(15), the outer surface of each of said elongated members
such as electrical power cables (9) for a longitudinal length of
between one and two times the mean outer diameter (d1, d2) of the
member being in abutting contact with and squeezed between at least
two of each supporting surfaces (15) so that a substantial part of
the weight of the member is supported by the first suspension (5),
and where the vertically extending supporting surfaces are provided
with beads (112, 120), and, where the wind turbine comprises drive
means for driving the pivoting of the nacelle (2) relatively to the
tower (1) and control means for controlling said drive means so
that the nacelle (2) will pivot less than a predetermined number of
turns relatively to a predetermined reference position of the
nacelle (2) so as to prevent excessive twisting of the power cables
(9), and where each of the plurality of elongated members such as
the electrical power cables (9) forms a down-hanging curve (11) and
is secured to the stationary part of the wind turbine at a vertical
position above the lowest part of the curve, the vertical extension
of the down-hanging curve at the reference position of the nacelle
being of a magnitude sufficient to ensure that the member will not
be exposed to excessive longitudinal tension due to the relative
shortening of the member caused by twisting of the member during
pivoting of the nacelle (2).
2. The wind turbine according to claim 1, wherein a plurality of
spacing devices (37) are arranged between the elongated members
such as the electrical power cables (9) with a vertical spacing
between neighbouring spacing devices (5), each spacing device being
arranged so as to maintain the members such as the power cables (9)
in a constant position in a horizontal plane of the spacing device
with a mutual spacing between the members.
3. The wind turbine according to claim 2, wherein the spacing
devices (37) are suspended from a vertically extending elongated,
flexible supporting means (7) of which an upper end is suspended
from the nacelle (2).
4. The wind turbine according to claim 3, wherein the supporting
means (7) is secured to an upper end of the first suspension
(5).
5. The wind turbine according to claim 1 and comprising a second
suspension (101, 113) being arranged at a lower vertical position
than the first suspension (5), the second suspension defining
substantially vertically extending supporting surfaces (111, 119),
the outer surface of each of said members such as the electrical
power cables (9) for a vertical length of at least four times the
mean outer diameter of the member being in abutting contact with
and squeezed between at least two of each supporting surfaces
(111,119) so that a substantial part of the weight of the member is
supported by the second suspension.
6. The wind turbine according to claim 5, wherein the second
suspension (101, 113) is being suspended from the nacelle (2).
7. The wind turbine according to claim 5, wherein the second
suspension (101, 113) is supported by a vertically extending
elongated, flexible supporting means (7) such as a wire, a rope or
a chain.
8. The wind turbine according to claim 7, wherein the supporting
means (7) is fastened at an upper end to the first suspension
(5).
9. The suspension to be used in a wind turbine according to claim
5, wherein the supporting surfaces (111,119) of the second
suspension (101, 113) are formed from a resilient material.
10. The suspension according to claim 9, wherein said resilient
material is plastic.
11. The wind turbine according to claim 1, further comprising a
fastening device (10) for fastening the members such as the power
cables (9) to the stationary part of the wind turbine, the
fastening device (19) defining substantially vertically extending
supporting surfaces (25), the outer surface of each of said members
such as the power cables (9) being for a vertical length of at
least four times the mean outer diameter of the member in abutting
contact with and squeezed between at least two of each supporting
surfaces (26, 29) so that a substantial part of the weight of the
loop of the member is supported by the fastening device (10).
12. A suspension for attaching elongated members (9) such as
cables, cords, wires or the like, said suspension comprising a
first clamping portion (101) having first clamping jaws (102) and a
second clamping portion (113) having second clamping jaws (114),
said clamping jaws (102, 114) being intended for clamping around
one of the members, and where the first clamping portion (101) and
the second clamping portion (113) may be displaced inwardly towards
each other and by securing means (121) may be secured around the
member, the second clamping jaws (114) extend inwards into the
first clamping jaws (102), that the first clamping jaws (102)
extend around the second clamping jaws (114) when the two clamping
portions (191,113) are assembled, that an inner surface (119) of
the second clamping jaws (114) extends in extension of an inner
surface (111) of the first clamping jaws (102), that an outer width
(b) of the second clamping jaws (114) is smaller than an inner
width (B) of the first clamping jaws (102), and that the first
clamping portion (101) and the second clamping portion (113) are
intended for being displaced linearly towards each other.
13. The suspension according to claim 12, wherein the inner surface
(111) of the first clamping jaws (102) has a substantially
semicircular shaped contour, that the inner surface (119) of the
second clamping jaws (114) has a substantially semicircular shaped
contour and that the inner surfaces (111, 119) of the jaws (102,
114) on the two clamping portions (101, 113) form a through-going
hole which is substantially circular when the clamping portions
(101, 113) are assembled.
14. The suspension according to claim 12, characterised in that the
inner surface (111) of the first clamping jaws (102) has a
substantially semicircular shaped contour, and that the inner
contour of the inner surfaces (111, 119) of the jaws (102,114) on
the two clamping portions (101, 113) form a through-going hole
which is substantially oval when the clamping portions (101,113)
are assembled.
15. The suspension according to claim 12, wherein the extension of
the first clamping jaws (102) is inwardly conical along an
extension outwardly towards an opening (103) of the jaw (102) and
that the extension of the second clamping jaws (114) is linear
along an extension outwardly towards an opening (115) of the jaw
(114).
16. The suspension according to claim 12, wherein the suspension
(101, 113) comprises a first clamping portion (101) and furthermore
comprises a first embodiment of a second clamping portion (113) and
a second embodiment of a second clamping portion (113), and that
both the first embodiment and the second embodiment of the second
clamping portion (113) each are capable of cooperating with the
first clamping portion (101).
17. The suspension according to claim 16, wherein the through-going
hole is substantially round when the first clamping portion (101)
co-operates with the first embodiment of the second clamping
portion (113) and that the through-going hole is substantially oval
when the first clamping portion (101) co-operates with the second
embodiment of the second clamping portion (113).
18. The suspension according to claim 12, wherein the clamping
portions (101, 113) are provided with ears (109, 117) extending
outwardly and sideways from the clamping jaws (102, 114) in a plain
substantially perpendicular to the extension of the clamping jaws
(101,114), that the ears (109) on the first clamping portion (101)
is opposite the ears (117) on the second clamping portion (113)
when the clamping jaws (102, 114) are assembled and that the ears
(109, 117) are provided with means (110, 118) for enabling mutual
securing between the ears (109,117).
19. The suspension according to claim 12, wherein the inner
surfaces (111, 119) of the clamping jaws (102, 114) are provided
with beads (112, 120) and that the beads (112, 120) extend
outwardly from the inner surfaces (111, 119) of the jaws (102, 114)
and inwardly in the through-going hole between the jaws (102, 114)
when the clamping portions (191,113) are assembled.
20. The suspension according to claim 12, wherein the clamping
portion (101) are provided with a tongue (104) extending outwardly
and backwards from the jaws (102) on the clamping portion (101) in
a plain substantially parallel to the extension of clamping jaws
(102), and that the tongue (104) is provided with means (105) for
securing of the clamping portion (101) to a holder (124)
characterised in that the clamping portion (101) is provided with
projections (108) extending outwardly and backwards from the jaws
(102) and that the projections (108) extend in a plain immediately
parallel to the tongue (104) and that the projections are intended
for abutting an edge of the holder (124) when the clamping portion
(101) is mounted to the holder (124).
21. The suspension according to claim 12, wherein a first clamping
portion (101) and a corresponding second clamping portion (113) are
mutually joined by a hinge connection and/or that partly a
plurality of first clamping jaws (102) and partly a plurality of
corresponding second clamping jaws (114) are mutually joined a
hinge connection.
22. The first holder (124) for holding of a plurality of elongated
members (9) such as cables, cords, wires or the like, said holder
comprising a plurality of suspensions according to claim 20,
wherein the holder (124) is provided with a plate (126) with means
for co-operation with the tongue (104) on the suspensions (101),
that the jaws (102) on the suspensions (101) extend outwardly from
the plate (126) when the suspensions (101) are mounted to the plate
(126) so that the through-going holes between the clamping jaws
(102, 114) extend substantially vertical and that the plate (126)
is provided with means (125) for securing of the plate (126) to a
construction so that the plate extends in a horizontal plane.
23. The second holder (50) for holding of a plurality of elongated
members (9) such as cables, cords, wires or the like, said holder
comprising a plurality of suspensions according to claim 20,
wherein the holder is provided with a plate (52) with means for
co-operation with the tongue (104) on the suspensions (101), that
the jaws (102) on the suspensions (101) extend outwardly from the
plate (52) when the suspensions (101) are mounted to the plate (52)
so that the through-going holes between the clamping jaws (102,
114) extend substantially vertical and that the plate (52) is
provided with means (51) for securing of the plate to a
construction so that the plate extends in an oblique plane in
relation to a horizontal plane.
24. The fourth holder constituting a means for securing a first
type of said holder (124) according to claim 20, further comprising
another stationary construction separate from the holder (124),
wherein said fourth holder comprises a rod with a first end being
attached to the plate (126) of the said first type of holder (124)
and a second end being attached to the stationary construction,
said first and second ends being attached by means of a linkage
provided at the said first type of holder (124) and at the
stationary construction and by which the rod is limited in its
movement in relation to the plate and in relation to the stationary
construction in such a way that the rod is movable in one vertical
plane only.
Description
[0001] This application is a Divisional of co-pending application
Ser. No. 09/880,904, filed on Jun. 15, 2001, which is a
Continuation of co-pending International PCT Application No.
PCT/DK99/00708, filed on Dec. 17, 1999, which designated the United
States, the entire contents of which are hereby incorporated by
reference and for which priority is claimed under 35 U.S.C. .sctn.
120; and this application claims priority of Application No. PA
1998 01661 filed in Denmark on Dec. 17, 1998 under 35 U.S.C. .sctn.
119.
FIELD OF THE INVENTION
[0002] The present invention relates to a wind turbine with a
suspension and such a suspension for attaching elongated members
such as cables, cords, wires or the like, said suspension
comprising a first clamping portion and a second clamping portion,
said clamping portions being intended for clamping around the
member, and where the first clamping portion and the second
clamping portion may be displaced inwards against towards each
other and by means of securing means may be secured around the
item. The invention also relates to a holder for such
suspension.
BACKGROUND OF THE INVENTION
[0003] U.S. Pat. No. 5,195,704 describes a clamp for securing a
cord or the like. The clamp comprises a body and a cover, each
provided with surfaces for supporting the cord. Each part comprises
a clamping portion and a through-going bead, extending within the
surface of the clamping jaw. The cover is displaceable in relation
to the body so that the clamping jaws are more or less tightly
engaged. Thus, it is possible to secure cords with different
diameters. The cover is displaced in relation to the body and is
secured in relation to the body by means of a bolt.
[0004] However, this clamp has certain drawbacks. Because of the
shape of the clamping jaws, where the inner surfaces of the
clamping jaws have a partly circular cross-section with a given
radius, it is not possible to secure cords with a smaller diameter
as well as cords with a large diameter, and specifically not as
well as cords with a diameter corresponding to the radius of the
inner surfaces of the clamping jaws. Furthermore, the way that the
body and the cover are mutually connected has the drawback that
there is a risk of tearing off any insulation of the cords because
of the pincers-movement made by the cover in relation to the body,
when the two clamping jaws are being displaced towards each
other.
[0005] U.S. Pat. No. 4,684,196 describes a clamp connector for
holding of electrical wires and for connecting of these. The
connector comprises a first and a second half portion which are
mutually joined and which are provided with at least two
corresponding grooves for taking up of the electrical wires. Each
of the two half portions is provided with transverse bridging
plates that are provided with sets of piercing teeth. The purpose
of the connector is to provide a means that is capable of better
securing the electrical wires, also even if the ends of the
electrical wires are exposed to a permanent deformation when the
ends are pushed together in the holder. Furthermore, it is a
purpose that the connector itself is not exposed to deformation
when the two half portions of the connector are mutually connected
and tightened towards each other.
[0006] This connector has actually the complete opposite purpose
than the present invention and accordingly this connector is
provided with means that are very different to the means of the
holder of the present invention. The purpose of the above-mentioned
connector is to penetrate the insulation of the wires and the wires
themselves in order to obtain the conducting contact between the
ends of the wires and the transverse bridging plates. Thus, a
severe and permanent deformation of not only the insulation but
also of the wiring itself is established with the connector of the
above-mentioned US-publication.
[0007] DE 2 650 145 describes a clamp for hanging up of electrical
cables extending horizontally between masts. The clamp comprises an
inner shelf clamping around the cable and an outer shelf
surrounding the inner shelf. The inner shelf consists of two halves
tightened together around the cable. Each of the two halves is
provided with jaws together forming a substantially semi-circular
cross-section, so that when the two halves of the inner shelf are
squeezed together then a substantially circular cross-section is
formed through which cross-section the electrical cable stretches.
The purpose of the holder is however to provide a holder minimising
the risk of water penetrating into the holder and which, if water
nevertheless did pass into the holder, assures that the water is
led out of the holder again.
[0008] This holder has more similarities with the present
invention. However, still a substantial drawback is envisaged. Each
of the two halves of the inner shelf has opposite end surfaces
being pushed towards each other when the two halves of the inner
shelf are being tightened together. There is a great risk of the
insulation of the electrical wires being squeezed between these
opposing surfaces. It is important to bear in mind, that the
diameter of the electrical wire may vary depending on the
manufacturer of the cables and depending on the type of cable and
due to different dimensions depending on temperature and humidity.
Especially in the case where the two halves are completely joined
and where the opposing surfaces are abutting each other when the
halves are joined, then there is an even greater risk of the
insulation being squeezed and damaged.
[0009] U.S. Pat. No. 5,794,897 describes a hanger for supporting
transmission lines such as coaxial cables and the like used in
antenna systems. The hanger comprises a clamping structure with two
gripping elements. The gripping elements of the clamping structure
grip the coaxial cables by means of notches provided on gripping
surfaces of the gripping elements. This is accomplished by securing
means such as bolt and nut, which tighten the two gripping elements
together. The gripping elements are also provided with snapping
elements for connecting said gripping elements so that the clamping
structure may be used for initially loosely clamping the cables and
subsequently firmly clamping the cables when the securing means are
tightened.
[0010] The document describes the possibility of gripping cables by
having beads on gripping surfaces of gripping elements. However,
the clamping structure still has the great disadvantage that the
outer insulation of the cables may be damaged when the gripping
elements are tightened. Because of the expressed need for firstly
loosely securing and subsequently firmly securing the cables to the
clamping structure, snapping means are provided. These may however
squeeze the insulation when the gripping elements are firmly
tightened around the cables. Furthermore, there is no mentioning of
the special problems occurring within wind turbine towers where the
cables may be twisted.
[0011] U.S. Pat. No. 4,545,728 describes a wind turbine with yaw
spring return means for returning the nacelle of the wind turbine
from a position to which it has been turned to the initial position
in order to prevent excessive twisting of the power cables and
control cables. The power cables and control cables extend loosely
and linearly downwards from the nacelle through a passage
constituted by an annular bearing to the tower. When the nacelle
rotates in relation to the tower, the cables will twist as well.
When the nacelle by means of the yaw spring returns to its initial
position the cables will unwind.
[0012] This document does however not disclose special means for
suspending the cables extending from the nacelle downward through
the passage to the tower. Thus, with no special suspension means
and with a twisting of the cables, then there is a great risk of
the cables disconnecting from whichever attachment means they may
be connected to. Also, cables extending form the nacelle and
downwards through high towers will experience that the weight of
the cables together with only a slight twisting of the cables may
cause the cables to disconnect in response to a combination of the
load from the weight of the cables just added a small force from
the slight twisting of the cables.
BRIEF DESCRIPTION OF THE INVENTION
[0013] It is the object of the present invention to provide a
suspension capable of securing cords, cables, wires, hoses and the
like with varying diameters with the same degree of securing, but
also securing these items in a better way and especially a
suspension for suspending the items vertically. Moreover, it is the
object of the invention to provide a suspension without the risk of
damaging the items or the insulation of the items.
[0014] The object is achieved by a wind turbine having a first
suspension characterised in that the wind turbine further
comprising at least a first suspension being suspended by the
nacelle, the first cable suspension defining substantially
vertically extending supporting surfaces, the outer surface of each
of said elongated members such as electrical power cables for a
longitudinal length of at least four times the mean outer diameter
of the member being in abutting contact with and squeezed between
at least two of each supporting surfaces so that a substantial part
of the weight of the member is supported by the first suspension.
The object may also be obtained by the suspension itself before
installation in the wind turbine.
[0015] The object may also be achieved by a wind turbine having a
second suspension characterised in that the wind turbine further
comprising at least a first suspension being suspended by the
nacelle, the first cable suspension defining substantially
vertically extending supporting surfaces, the outer surface of each
of said elongated members such as electrical power cables for a
longitudinal length of between one and two times the mean outer
diameter of the member and that the vertically extending supporting
surfaces are provided with beads, and the member being in abutting
contact with and squeezed between at least two of each supporting
surfaces so that a substantial part of the weight of the member is
supported by the first cable suspension. The object may also be
obtained by the suspension itself before installation in the wind
turbine.
[0016] By the present invention a means is provided for suspending
elongated members such as electrical power cables, hydraulic hoses,
ropes and the like which eliminates the risk of as example cables
detaching from the nacelle causing failure in delivering the
electrical power from the generator system of the wind turbine to
the user. This is especially a risk in tall wind turbines that are
becoming more and more common because of an increasing demand for
wind turbines with larger and larger electrical capacity. Also,
when using wind turbines with higher towers there is the risk of
the electrical cables twisting inside the tower when the nacelle is
pivoted in relation to the tower. In the following reference will
mainly be made to electrical power cables as an example of
elongated members to be suspended. However, the reference to
electrical power cables does not limit the type of elongated
members that the invention may be used for.
[0017] By letting the clamping portions extend around each other
and by letting the clamping portions being assembled linearly and
by letting the inner surface of the clamping portions extend in
continuation of the inner surface of the jaws on the first clamping
portion, it is achieved that no pincers-movement will occur when
the clamping portions are assembled around e.g. the cable. Moreover
it is achieved that it is possible to leave a large part of the
inner surface of the clamping portions free so that the clamping
around the cable can take place independently of the mutual
engagement between the clamping portions.
[0018] In a preferred embodiment of invention the suspension is
shaped in such a manner that the inner surface of the first
clamping portion has a substantially semicircular contour, that the
inner surface of the second clamping surface has a substantially
semicircular contour, and that in a first application situation the
clamping portions are secured so that the inner surfaces of the two
clamping portions form a through-going hole which is circular when
the clamping portions are assembled, and in a second application
situation are secured so that the inner contour of the inner
surfaces of the two clamping surfaces form a through-going hole
which is oval when the clamping portions are assembled.
[0019] By providing through-going holes between the jaws on the
clamping portions, being either round or oval, with said clamping
portions it is made possible to secure e.g. cables with different
diameters. In a preferred embodiment the suspension is
characterised in that the suspension comprises a first clamping
portion and furthermore comprises a first embodiment of a second
clamping portion and a second embodiment of the second clamping
portion, and that both the first embodiment and the second
embodiment of the second clamping portion each are capable of
co-operating with the first clamping portion, and where the
through-going hole is substantially round when the first clamping
portion cooperates with the first embodiment of the second clamping
portion, and the through-going hole is substantially oval when the
first clamping portion cooperates with the second embodiment of the
second clamping portion.
[0020] By using the said first clamping portion but various second
clamping portions, it is possible to obtain same large variation in
diameter of e.g. those cables which the suspension is capable of
securing. It is an advantage that only a single embodiment of the
first clamping portion is capable of co-operation with various
embodiments of the second clamping portion as it is then possible
to retain the first clamping portion attached to e.g. a holder, and
at the same time it is possible to replace the second clamping
portion in order to secure e.g. different cables with different
diameters.
[0021] The clamping portions according to the present invention are
preferentially manufactured and are preferentially used as separate
clamping portions. In an alternative embodiment, by the manufacture
and the use of the clamping portions it will however be possible to
join the first clamping portion with the second clamping portion by
means of a kind of hinge device. This may have the advantage that
already at the manufacture it is made easier to figure out, in
connection with the later use, which clamping portions belong
together, and that the first clamping portion and the second
clamping portion are already joined together when the cable are
mounted between the clamping portions, and the ears of the clamping
portions are subsequently squeezed together by means of the bolts
which extend through the holes in the ears.
[0022] Moreover, it will be possible to join a plurality of first
and a plurality of second clamping portions so that a row of first
clamping portions and a row of second corresponding clamping
portions are formed. This opens up the possibility of delivering
the clamping portions in tapes comprising several clamping portions
of the same type. The type of clamping portion, which is suitable,
can then be broken off or cut off the tape with the clamping
portion of the type in question. It will also be possible to
provide a combination of connections between a first clamping
portion and a second clamping portion and connections in a tape
partly between a plurality of first clamping portions and partly
between a plurality of second corresponding clamping portions.
[0023] In a preferred embodiment a plurality of cable spacing
devices are arranged between the electrical power cables with a
vertical spacing between neighbouring spacing devices, each spacing
device being arranged so as to maintain the power cables in a
constant position in a horizontal plane of the spacing device with
a mutual spacing between the cables.
[0024] By using spacing devices it is intended to keep a distance
between the cables. Because of the electrical current running
through the cables the cables are slightly heated. However if
perhaps six cables are hanging from the nacelle and down through
the tower, the heating will take place of all six cables at the
same time. In this case it is especially necessary to maintain a
distance between the cables. It is also necessary to maintain a
distance between the cables in order to eliminate the risk of wear
of the insulation of the cables. If the cables are passed down
through the tower in a bundle the cables will slide along each
other when the nacelle is pivoting in relation to the tower. Using
spacers ensures that this mutual sliding is avoided.
[0025] In a further preferred embodiment the plurality of
electrical power cables forms a down-hanging curve and is secured
to the stationary part of the wind turbine at a vertical position
above the lowest part of the curve, the vertical extent of the loop
at the reference position of the nacelle being of a magnitude
sufficient to ensure that the cable will not be exposed to
excessive longitudinal tension due to the relative shortening of
the cable caused by twisting of the cable during pivoting of the
nacelle.
[0026] By securing the cables to the stationary part as example by
using a cable support device that is secured to the inner wall of
the tower, the cables will be led down through most of the tower
along the inner wall of the tower. This makes it possible to
eliminate the risk of the cables twisting excessively because the
cables are hanging freely in a downwards curve before being led
past the suspension, said downwards curve taking up the tensioning
of the cable when the nacelle is pivoting in relation to the tower.
Also, it eliminates the inconvenience of having the cables to take
up space in the center of the tower.
[0027] Further scope of the applicability of the present invention
will become apparent from the detailed description given
hereinafter. However, it should be understood that the detailed
description and specific examples, while indicating preferred
embodiments of the invention, are given by way of illustration
only, since various changes and modifications within the spirit and
scope of the invention will become apparent to those skilled in the
art from this detailed description.
BRIEF DESCRIPTION OF DRAWINGS
[0028] The invention will now be described with reference to the
accompanying drawings, which are given by way of illustration only,
and thus are not limitative of the present invention, and
wherein:
[0029] FIG. 1 is a sectional view of a wind turbine tower with a
part of a nacelle shown above the top of the tower and with a cable
suspension according to the invention,
[0030] FIG. 2 is a second sectional view of a wind turbine tower
with a cable suspension according to the invention and with a
fastening device according to the invention
[0031] FIG. 3 is a longitudinal view of a cable suspension
according to the invention,
[0032] FIG. 3A is a longitudinal view of an alternative cable
suspension according to the invention
[0033] FIG. 4 is a sectional view of a supporting surface of the
cable support
[0034] FIG. 5 is a plane view of the supporting surface of the
cable support
[0035] FIG. 6 is a sideways view of a fastening device according to
the invention
[0036] FIG. 7 is a top view of the fastening device according to
the invention
[0037] FIG. 8 is a plane view of a cable distance device according
to the invention,
[0038] FIG. 9 is a view from beneath of an embodiment of a first
clamping portion,
[0039] FIG. 10 is a sectional side view through the first clamping
portion,
[0040] FIG. 11 is a crosswise sectional view through the first
clamping portion,
[0041] FIG. 12 is a perspective view as seen diagonally from
beneath of the first clamping portion,
[0042] FIG. 13 is a view from beneath of an embodiment of a second
clamping portion,
[0043] FIG. 14 is a side view through the second clamping
portion,
[0044] FIG. 15 is crosswise view through the second clamping
portion,
[0045] FIG. 16 is a perspective view as seen diagonally from
beneath of the second clamping portion,
[0046] FIG. 17 is a perspective view of engagement between the
first clamping portion and a first embodiment of the second
clamping portion in a first application situation,
[0047] FIG. 18 is a perspective view of engagement between the
first clamping portion and a second embodiment of the second
clamping portion in a second application situation,
[0048] FIG. 19 is a perspective view of engagement between a second
embodiment of the first clamping portion and a third embodiment of
the second clamping portion,
[0049] FIG. 20 is a perspective view of a first type of holder with
a plurality of suspensions according to the invention mounted on a
plurality of polygonal plates
[0050] FIG. 21 is a photograph of a second type of holder with a
plurality of suspensions according to the invention mounted on a
polygonal plates,
[0051] FIG. 22 is a sketch of a third type of holder for ensuring
the maintenance of the cables in a horizontal direction,
[0052] FIG. 23 is a photograph of a fourth type of holder also for
ensuring the maintenance of the cables in a horizontal direction,
and
[0053] FIG. 24 and FIG. 25 are a drawings showing a way that
suspensions may be temporarily secured to intermediate floors in
the wind turbine tower.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0054] FIG. 1 shows a stationary structure of a wind turbine. The
stationary structure comprises a tower 1. A nacelle 2 is placed on
top of the tower 1. The nacelle 2 is pivotable around a vertical
axis M along the center of the tower 1. A ladder 3 is mounted to
the nacelle 2 and extends down into the tower 1 past a passage 4
between the nacelle 2 and the tower 1. A cable suspension 5 is
fastened to the ladder 3 and accordingly also fastened to the
nacelle 2. The cable suspension has a length L being at least four
times the diameter of a cable (see FIG. 3). The cable suspension 5
is fastened to the ladder 3 by means of a linkage 6 being able to
swing freely in just one vertical plane perpendicular to the plane
of the paper. A wire 7 or a rope extends from the cable suspension
5 further down through the tower 1. The wire 7 or rope is provided
with cable spacing devices 8 that are distributed evenly down the
wire 7 or rope. The cable spacing devices 8 are intended for
maintaining a distance between cables extending from the cable
suspension 5 down through the tower 1. A total of four cable
spacing devices 8 are distributed with equal distance between the
number of devices. A depiction of a cable spacing device seen
parallel with the longitudinal axis M is shown in FIG. 8. For the
sake of clarity no cables are shown in FIG. 1.
[0055] FIG. 2 shows the stationary structure of a wind turbine. The
stationary structure also comprises the tower 1. A single cable 9
is shown extending form the cable support that is fastened to the
ladder 3. The cable 9 extends down through the tower 1. Partly down
the tower the cable is supported by a fastening device 10 (see FIG.
6 and FIG. 7). The fastening device 10 is secured to the inner wall
of the tower 1. The cable 9 shows a downward curve 11 along which
the cable is hanging freely and an upward curve 12 along which the
cable 9 is supported by the fastening device 10. The fastening
device 10 has a supporting curved plate (see FIG. 6 and FIG. 7) on
which the cable 9 is lying. After having passed the curved plate
the cable 9 is fastened to the fastening device 10 by means of
fastening plates (see FIG. 6 and FIG. 7). By providing a downwards
curve 11 along which the cable 9 is hanging freely it is prevented
that a tensioning of the cable 9 when the nacelle 2 is pivoting in
relation to the tower 1 will cause the cable to be excessively
tensioned and torn apart.
[0056] FIG. 3 shows a cable suspension 5 according to the
invention. The cable suspension 5 is shown parallel with a
longitudinal axis of the cable suspension, said longitudinal axis
extending perpendicular to the plane of the paper and being
vertical, when the cable suspension 5 is placed in the tower 1. The
cable suspension 5 comprises an inner supporting rod 13 with a
certain special outer curvature 14 and outer supporting plates 15
also with a certain special outer curvature 16. The inner
supporting rod 13 and the outer supporting surfaces 15 are mutually
connected by a bolt 17 being secured to the inner rod 13 and
extending through holes (see FIG. 4 and FIG. 5) in the supporting
plates 15. The supporting surfaces 15 may be moved along the bolt
17 in a direction along the bolt, and the supporting plates 15 is
maintained in place in relation to the bolt by nuts 18 having a
cross section being bigger than the hole (see FIG. 4 and FIG. 5) in
the supporting plates 15. Cables 9 are placed between the inner rod
13 and the outer surfaces 15. Due to the certain special outer
curvatures 14, 16 of the rod 13 and the supporting plates 15 the
inner rod 13 is pressed against the insulation of the cable 9. A
frictional layer 19 on the supporting plates 15 is abutting the
insulation of the cable 9 opposite where the curvature 14 of the
inner rod 13 is pressed against the insulation of the cable 9.
Thereby the cable is fastened to the cable suspension 5 without the
risk of sliding in a direction perpendicular to the plane of the
paper along the inner rod 13 and along the outer supporting plates
15.
[0057] In the embodiment shown of the cable suspension 5, the cable
suspension is supporting six cables 9 with a large diameter d1
using three curvatures 14 on the inner rod 13 and using three outer
supporting plates 15. The cable suspension 5 is also supporting two
cables 9 having a medium diameter d2 and four cables having a small
diameter d3 using the rear side of the before-mentioned outer
supporting plates and the special curvature 16 of further outer
supporting plates 15 that are maintained in place in relation to
the bolts outwardly in relation the before-mentioned supporting
plates 15. The number of cables 9 and the diameter d1,d2,d3 of the
cables 9 supported by the cable suspension 9 are optional. It is
also possible to exclude the use of the further outer supporting
plates 15 if the number of cables 9 being supported by the cable
suspension 5 may be supported by the supporting plates 15 only that
are keeping the largest cables in place.
[0058] FIG. 3A shows an alternative embodiment of a cable
suspension 5. The cable suspension 5 shown in FIG. 3A has many
similarities to the cable suspension shown in FIG. 3. However,
while the cable suspension shown in FIG. 3 primarily has an inner
rod made of plastic, and has supporting plates coated with rubber
or the like, then the cable suspension shown in FIG. 3A is made of
steel or other metal, both the inner rod and the supporting
surfaces. Neither the inner rod 13 nor the supporting plates 15 are
coated with rubber or the like. The metal that the rod 13 and the
plates 15 are made of may be coated with a corrosion inhibiting
means such as a zinc coating, but the coating is for inhibiting
corrosion and is not for increasing friction. Also, the design of
the inner rod 13 and of the supporting plates 15 is simpler and is
not provided with specially designed curvatures. The inner rod 13
and the supporting plates are just made of plain metal plates
individually joined and bent in order to establish the design of
the rod 13 and the supporting plates 15 as shown. The cable
suspension in FIG. 3A also has bolts 17 and nuts 18 for keeping the
supporting plates in place in relation to the inner rod 13.
[0059] FIG. 4 and FIG. 5 are a sectional view and a plane view,
respectively, showing the design of the outer supporting plate 15
(see FIG. 3). The outer supporting plate 15 has a curvature 16 that
is adapted to support the outer surface of a cable such as it is
shown in FIG. 3. The supporting plate 15 has an interior plate 20
made of metal with a central plane part 21 and outer bent parts 22.
The inner plate 20 has two holes 23 through which the bolts (see
FIG. 3) can protrude. The inner plate 20 also has several
perforations 24 that limit the weight of the plate 20. A frictional
layer 19 such as a plastic or rubber material is moulded around the
inner plate 20. The frictional layer 19 forms the certain special
curvature 16 of the supporting plate 15.
[0060] Optionally, the frictional layer may be omitted thereby
constituting plane metal plates such as those used in the
suspension shown in FIG. 3A. In order to maintain a satisfactory
friction then the perforation will normally be omitted too in order
to have en even and unbroken surface against which the outer
surface of the cables is supported. However, if the cables are of a
relatively small diameter, or if the cables that are to be
suspended are not long, then a satisfactory friction may be
obtained also if the perforations are present.
[0061] Nevertheless, it will be possible to combine the type of and
the design of the inner rod shown in FIG. 3 with either the
supporting plates shown in FIG. 5 and FIG. 5 as is the case of the
suspension shown in FIG. 3 or with a type of and design of plates
as mentioned above and as shown as part of the suspension shown in
FIG. 3A. It will also be possible to combine the inner rod shown in
FIG. 3A with a type of plate as mentioned above as is the case of
the suspension in FIG. 3A or with a type of plate as shown in FIG.
4 and FIG. 5.
[0062] FIG. 6 and FIG. 7 are a sideways view and a top view,
respectively, of a fastening device 10 for fastening of cables 9 to
the tower 1 (see FIG. 2). The fastening device 10 has side plates
25 and between the side plates an upward curved plate 26 is
stretching. At the one side of the side plates 25, which in the
figure is the right hand side, tongues 27 with holes 28 are
provided for securing by means of bolts or the like the fastening
device 20 to the inner wall of the tower 1 as shown in FIG. 2. Also
at the same one side of the fastening device 10 two bars 29 are
provided between the side plates 25. The cables that are to be
mounted are led past the bars 29 and afterwards over the curved
plate 26 so that the cables are maintained in place between the
bars 29 and the plate 26.
[0063] At the other side, which in the figure is the left-hand
side, the fastening device 10 is provided with fastening means 30
for securing cables to the fastening device. The fastening means 30
comprises a base plate 31 and fastening plates 32 that are placed
at a distance from the base plate 31. The distance is established
by means of bolts 33 along which the fastening plates 32 can be
displaced towards the base plate 31 or away from the base plate 31.
The cables are intended for being fastened preferably in pairs
between the base plate 31 and a fastening plate 32. If the cables
have a relatively small diameter, the fastening plate 32 is
displaced further towards the base plate 31 and a nut 34 is
tightened. Opposite, if the cables have a relatively large
diameter, the nut 34 is loosened and the fastening plate 32 is
displaced further away from the base plate 31 whereafter the nut 34
is tightened when the cables are in place.
[0064] FIG. 8 is a plane view of a cable spacing device 8 (see FIG.
1) for maintaining a mutual distance between the cables hanging
down through the tower. The cable spacing device is suspended down
along a wire 7 or a rope as shown in FIG. 1. The device 8 has a
polygonal or circular circumference and is provided with slots
35,36 that extend from the circumference 37 towards the center 38
of the device. The center 38 of the device is provided with a hole
39 through which the wire 7 (see FIG. 1) or rope onto which the
device is suspended can run.
[0065] The device has a first type of slots 35 that extend from the
circumference 37 and only a smaller distance s1 towards the center
38. The first type of slots 35 have an opening 39 at the
circumference 37 and lead into a partly circular section 40 having
a larger diameter D adapted for holding cables with substantially
such a diameter. The device has a second type of slots 36 that
extend from the circumference 37 and a greater distance s2 towards
the center 38. The second type of slots 36 also have an opening 41
at the circumference 37 and lead into a partly circular section 42
having a smaller diameter d adapted for holding cables with
substantially such a diameter. All of the slots 35,35 are provided
with beads 43,44 that form a sort of closing of the opening 39,41
into the slots 35,36. The device is made from a slightly resilient
material so that the distance between the beads 43,44 is enlarged
and the opening 39,41 of the slots 35,36 is widened when the cables
are to be introduced into the slots 35,36. Alternatively the
spacing device 8 can be made of a material being less resilient
such as metal and the introduction of the cables into the slots
35,36 past the beads 43,44 is obtained by squeezing the insulation
of the cables past the beads 43,44.
[0066] FIGS. 9,10,11 and 12 show a first clamping portion 101 for a
suspension according to the invention. The clamping portion 101
comprises two jaws 102, which along a first stretch 1 run in a
semicircle, and which along second stretches m run rectilinearly in
continuation of the semicircle. The semicircle has a diameter d.
The second stretches m may run parallel with each other and
parallel with a longitudinal axis of the extent of the jaws.
Alternatively, the second stretches m may converge a little towards
each other towards an opening 3 of the clamping portion. It is the
jaws 102 that form the opening 103, and between the jaws 102 along
the stretch m there is a inner width B. In the shown embodiment the
inner width B is equal to the diameter d1 of the semicircle within
the first stretch 1. However, alternatively the inner width is a
little smaller, as example 1 mm smaller, than the diameter d of the
semicircle. This has the advantage that when introducing the cables
into the clamping portion through the opening, then the cables meet
a small resistance when having to pass the opening. Having overcome
this resistance the cables are kept in place by a resistance
towards slipping out through the opening.
[0067] A tongue 104 extends outwards from the jaws 102 in the
opposite direction of the opening 103 on the jaws 102 and parallel
with the longitudinal axis A of the extent of the jaws 102. The
tongue 104 is intended for clamping the clamping portion 101 onto a
holder (see FIG. 20), and for that purpose the tongue 104 is
provided with a through-going hole 105 for the mounting of a bolt
(not shown) or the like clamping means through the hole 105.
[0068] In the embodiment shown (see FIG. 10) the hole is formed so
as to accommodate the head of a bolt that is passed through the
hole. This is done by dividing the hole in a lower part with a
smaller diameter and an upper part with a larger diameter for
accommodating the head of the bolt. Alternatively, the hole may in
stead be shaped so as to accommodate a nut for the bolt. This may
be done by shaping the lower part with a larger diameter for
accommodating the nut and the upper part with a smaller diameter.
In the latter case, the lower part may be hexagonal so that the nut
is accommodated with a snug fit in the lower part of the hole.
Thereby, the hole itself will be able to restrict the nut from
rotating when the bolt is turned during mounting of the clamping
portion to the holder (see FIG. 20) and thus eliminating the need
for a wrench for the nut and only needing a wrench or a screwdriver
for the bolt.
[0069] On each side the tongue 104 has a larger thickness forming
reinforcing ribs 106, and the tongue 104 also has a larger
thickness of material around the hole in order to form a
strengthening 107 of the hole.
[0070] On the rear side the jaws 102 have two projections 108,
extending outwards from the jaws 102 in the opposite direction of
the opening 103 of the jaws 102. The projections 108 extend
outwards on each side of the tongue 104, and are intended for
forming abutment with a plate (see FIG. 20) on a holder for
mounting a plurality of clamping portions.
[0071] On each side of the jaws 102 the clamping portion 101 is
provided with ears 109, extending outwards in a plane p
perpendicular to the longitudinal axis A of the jaws 102. The ears
109 are intended for being positioned opposite corresponding ears
on the other clamping portion (see FIGS. 13-20). The ears 109 are
provided with through-going holes 110 (see FIG. 11) for the
mounting of a bolt (not shown) or the like fastening means through
the hole 110. The bolt is intended for clasping together the ears
109 of the shown first clamping portion 101 and the ears of the
second clamping portion (see FIGS. 13-20) in order to clamp the
jaws on each of the clamping portions towards each other.
[0072] On an inner side 111 the jaws 102 are provided with a bead
112, extending inwards between the jaws 102. The beads 112 are
intended for being pressed into the plastic or rubber insulation of
a cable (not shown) or a cord secured in the suspension 101. The
beads 111 result in a substantially better securing of a cable or a
cord, especially in those cases where the cable or the cord hangs
vertically in the suspension 101.
[0073] FIGS. 13,14,15 and 16 show a second clamping portion 113 for
a suspension according to the invention. The clamping portion 113
also comprises jaws 114, which run along a stretch n in a circle
curve smaller than a semicircle. The jaws form an opening 115, and
between the jaws 114 there is an outer width b. The outer width b
of the jaws is smaller than the inner width B of the jaws on the
first clamping portion (see FIGS. 9-13). Along the stretch n the
outer sides 116 of the jaws 114 run conically with a conicity c
turned towards the opening for the jaws 114. This means that the
jaws 114 of the shown second clamping portion 113 are capable of
stretching into the jaws 102 of the first clamping portion 1 (see
FIG. 9).
[0074] On each side of the jaws 114 the clamping portion 113 is
provided with ears 117, extending outwards in a plane q
perpendicular to the longitudinal axis A of the jaws 114. The ears
117 are intended for being positioned opposite corresponding ears
109 of the first clamping portion 101 (see FIGS. 9-13). The ears
117 are provided with through-going holes 118 for the mounting of a
bolt (not shown) or the like fastening means through the hole 118.
The bolt is intended for clasping together the ears 117 of the
second clamping portion 113 and the ears 109 of the first clamping
portion 101 (see FIGS. 9-13) in order to clamp the jaws of each of
the clamping portions towards each other.
[0075] The jaws 114 are, like the jaws of the first clamping
portion, on an inner side 119 provided with a bead 120 extending
inwards between the jaws 114. The beads 120 result in a
substantially better securing of a cable or a cord, especially in
those cases where the cable or the cord hangs vertically in the
suspension. In the embodiments shown, see especially the
cross-section in FIG. 15, there is a space S between the ears 117.
However, in a preferred embodiment this space S is being provided
with flanges extending between the ears, in the plane of the paper
as seen in FIG. 15 and perpendicular to the plane of the paper as
seen in FIG. 14, so as to mutually connect the ears. It has turned
out that when clasping the shown second clamping portion together
with the first clamping portion (see FIGS. 9-12) and fastening the
clamping portion together by means of a bolt (not shown) there is a
risk of the ears 117 being bent in relation to each other and in
relation to the jaws 114. By providing a number of flanges along
the length of the second clamping portion, then the ears are
mutually fixed in relation to each other and the ears are also
fixed in relation to the jaws. Thereby the risk of the ears bending
is avoided.
[0076] In alternative embodiments, it is rendered possible for both
the first clamping portion and the second clamping portion to
provide other means than beads, e.g. buttons formed in the jaws.
The application of such means and the shaping of these depend on
the type of flexible item, such as cables, cords, wires, robes
etc., which the suspension has to carry, and whether the suspension
has to carry the item vertically, horizontally or in any other
direction between vertically or horizontally. It is also possible
to leave out any kind of means so that the jaws are quite plane on
the inside.
[0077] The first clamping portion and the second clamping portion
are preferably made from polyamide, which is fibre-strengthened,
preferably with glass fibres. Polyamide has the advantage that it
can absorb and emit moisture so that the securing of the cable is
maintained independently of the air humidity in the surrounding
atmosphere.
[0078] FIG. 17 shows a first clamping portion 101 and a first
embodiment of the second clamping portion 113 in mutual engagement
in a first application situation for cables with small diameter.
The cable intended for being secured in the suspension is however
left out for the sake of the illustration. The jaws 114 of the
second clamping portion 113 extend inwards into the jaws 102 of the
first clamping portion 101. The second clamping portion 13 has jaws
extending along a given larger circle curve with a diameter d2.
Bolts 121 extend through the holes 110, 118 in the ears 109, 117 of
the first clamping portion 101 and the second clamping portion 113
respectively.
[0079] When, as in the shown application situation, the clamping
portions are clamped towards each other by tightening the bolts,
the through-going hole 122, which is formed between the jaws 102,
114 of the two clamping portions 101, 113, will have a
substantially circular cross section. If the cable, which is
intended for extending through the hole 122 formed between the jaws
102, 114, has a diameter slightly smaller than the diameter d1 of
the semicircle of the jaws 102 on the first clamping jaw (see FIGS.
9-13), said cable will be secured along practically the whole
radius of the cable. In a specific embodiment, the suspension shown
in FIG. 17 is capable of securing cables with a diameter of between
34 mm and 39 mm.
[0080] FIG. 18 shows a first clamping portion 101 and a second
embodiment of the second clamping portion 113 in mutual engagement
in a second application situation for securing cables with larger
diameter. The cable intended for being secured in the suspension is
however left out for the sake of the illustration. The jaws of the
second clamping portion 113 extend inwards into the jaws 102 of the
first clamping portion 101. The second clamping portion 113 has
jaws 114 extending along a given smaller circle curve d.sub.3.
Bolts 121 extend through the holes 110, 118 in the ears 109, 117 of
the first clamping portion 101 and the second clamping portion 113,
respectively.
[0081] When, as in the shown application situation, the clamping
portions 101,113 are clamped towards each other by the tightening
the bolts 121, the through-going hole 123 formed between the jaws
102, 114 of the two clamping portions 101, 113, will have a
substantially oval cross section with a semicircle in one end
formed by the jaws 102 of the first clamping portion 113, and a
smaller circle curve in the other end formed by the jaws 114 of the
second clamping portion 113. If the cable intended for extending
through the hole 123 formed between the jaws 102, 114 has a
diameter, which is practically equal to the diameter d of the jaws
102 of the first clamping portion 101, said cable will be secured
along practically the whole radius of the cable. In a specific
embodiment, the suspension shown in FIG. 18 is capable of securing
cables with a diameter of between 41 mm and 46 mm.
[0082] FIG. 19 shows a second embodiment of the first clamping
portion and a third embodiment of the second clamping portion in
another application situation which is comparable with the other
application situation described in FIG. 18. The difference between
the clamping portions in FIG. 19 and the clamping portions in FIG.
18 is merely that the dimensions of the clamping portions in FIG.
19 are smaller than the dimensions of the clamping portions in FIG.
18. This means that the clamping portions in FIG. 19 are capable of
securing cables having a smaller diameter than the cables that the
suspension in FIG. 18 is capable of securing. In a specific
embodiment, the suspension shown in FIG. 19 is capable of securing
cables with a diameter of between 21 mm and 24 mm.
[0083] It is shown in all the FIGS. 17-19 that the bolts extending
through the holes in the ears have a length so that the bolts just
extend to the far side of the nut. Thereby the bolt will not pass
the nut and accordingly the end of the nut will not take up any
space when the clamping portions are clasped together. However, if
at least one of the bolts have a length being substantially longer
than the bolts shown then the bolt in question may function as a
hinge between the first and the second clamping portion. If the
bolt is longer then it will be possible to assemble the bolt and
the nut but still having the opportunity to pull the first and the
second clamping portions form each other for insertion of a cable
into the jaws of the first clamping portion.
[0084] It is of great advantage to have the possibility to keep the
first and the second clamping portion together before suspension of
cables. Thereby there is no risk of dropping the second clamping
portion in an attempt to hold both the cable and the second
clamping portion in place while at the same time having to tighten
the bolts. Suspension of a cable in the clamping portions by use of
a long bolt as hinge takes place by firstly assembling one long
bolt with the corresponding nut, then pulling the first clamping
portion as far from the first clamping portions as the assembling
of the long bolt and nut permit, then inserting the cable into the
jaws of the first clamping portion, then inserting the jaws of the
second clamping portion into the jaws of the first clamping
portion, and finally assembling the other perhaps shorter bolt and
nut and tightening both bolts and both nuts for clasping the
clamping portions together around the cable.
[0085] FIG. 20 shows a first type of holder 124 for mounting a
plurality of suspensions according to the invention. The holder 124
consists of a longitudinal carrying beam 125 and plate sections 126
attached to the carrying beam 125 at regular intervals. The
suspensions are attached to the plate sections 126 by means of
bolts 127. Thus, the holder 124 forms a kind of carousel with
suspensions according to the invention. The plate sections 126
extend in planes P perpendicularly to the longitudinal axis C of
the carrying beam 125. The shown holder 124 is intended for
securing cables hanging vertically. With a holder 124 it is
moreover secured that the cables are not in physical contact with
each other, and thus no heat can be transferred between the
cables.
[0086] With the shown suspensions and the shown number of
suspensions it is possible to secure five cables with a small
diameter and five cables with a large diameter. By providing three
plate sections, which are arranged parallel to each other and with
suspensions placed in continuation of each other, it is possible to
secure the cable at three different places in continuation of each
other in order to increase the securing and to ensure that the
cables are secured even if one of the suspensions should break.
[0087] By means of the projections on the rear side of the jaws on
the first clamping portion (see FIGS. 17-20), it is achieved that
the suspensions cannot be considerably displaced sideways around an
axis of rotation O through the bolts which extend through the hole
in the tongue and which secure the suspensions to the plate
sections. In alternative embodiments, it will be possible to apply
a holder with more or fewer plate sections arranged parallel along
the carrying iron and to mount fewer suspensions on each plate
section.
[0088] For the shown holder with a plurality of first clamping
portions and second clamping portions mounted on and to the holder,
the above mentioned alternative manufacture of clamping portions
where a first clamping portion and a corresponding second clamping
portion are mutually joined at the manufacture by a kind of hinge
connection, would be a suitable embodiment of the clamping
portions. Also the above mentioned embodiment where a number of
first clamping portions and a number of corresponding second
clamping portions are mutually joined at the manufacture would be
suitable for a holder to which a plurality of clamping portions
have been attached. The hinge connection can have different shapes,
depending on the necessary strength and the required physical size
of the hinge connection.
[0089] The invention is described above with reference to specific
embodiments of the first clamping portion and the second clamping
portion. It will be possible to apply clamping portions with other
means than opposite ears in order to keep the clamping portions
clamped against each other. Moreover, it will be possible to secure
the clamping portions in another way than by providing the first
clamping portion with a tongue. Finally, it will be possible to let
the jaws in the clamping portions extend over a larger or smaller
length in order to establish a more or less firm securing of the
cable between the jaws. If the clamping portions e.g. are applied
for the securing of a cable hanging horizontally, it will not be
necessary to secure the cable as firmly as when the cable is
hanging vertically.
[0090] FIG. 21 is a photograph of a pair of second type of holder
50. This holder 50 is not intended for being suspended but is
intended, as shown, for being fastened to a stationary part of the
wind turbine, in the embodiment shown fastened to the inner wall of
the wind turbine tower 1 by means of braces 51. However, a plate 52
similar to the plate 126 for the first type of holder 124 shown in
FIG. 20 is also a part of the second type of holder. Thus, the
mounting of the suspensions with the clamping portions (see FIGS.
17.19) to the plate 51 of the holder takes place the same way as is
described for the first type of holder.
[0091] As shown, the second type of holder 51 may have the plate
orientated in different angular directions in relation to the
fastening means that are secured to the inner wall of the wind
turbine tower. The lower one of the holders has the plate
orientated horizontally. The upper one of the holders has the plate
orientated obliquely, perhaps in an angel V of 45.degree. in
relation to horizontal or vertical. However, other angels obliquely
to horizontal or vertical may be used in stead. As can be seen from
the figure, it is possible to bend the cables in a controlled
manner by selecting a proper angel that the plate of the upper
holder is orientated obliquely and by selecting a proper distance
between the lower holder and the upper holder.
[0092] FIG. 22 is a sketch of a third type of holder 53 for holding
the cables in a horizontal direction. The holder has an annular
member 54 that is intended for stretching round the cables in
places in between the suspensions described above. The third type
of holder 53 also has two legs 55 that are to be secured to the
inner wall of the wind turbine tower or secured to a latter
stretching upwards through the wind turbine tower. In high winds,
then the wind turbine tower will show dynamic oscillations with a
certain given natural vibration. When the wind turbine tower is
showing natural vibration, then the cables stretching from the
nacelle and down through the tower will also start showing dynamic
oscillations.
[0093] However, the natural vibration of the cables is different
than the natural vibration of the tower. Therefore the cables will
start swinging some distance from side to side within the tower and
with a certain amplitude. In order to ensure that the swinging from
side to side of the cables is not exaggerated to an extend that is
not desirable, then the third type of holder may be used. The third
type of holder 53 will maintain the swinging of the cables within
the annular member 54 of the holder. If the diameter of the annular
holder is the same as that of the bundle of cables when these are
suspended from the suspensions, then swinging of the cables can be
completely avoided.
[0094] FIG. 23 is a photograph of a fourth type of holder. The
holder consists of a rod 56 that is placed between a stationary
part of the wind turbine and a first type of holder 124 that is
suspended from the nacelle. The rod may as example be secured
between the inner wall of the tower or items secured to the inner
wall and a first type of holder being the lowest of the first type
of holders that is suspended from the nacelle. The rod is rigid but
is joined to the stationary part and the suspended first type of
holder in a way so that the rod may swing upwards and downwards but
is restricted from swinging sideways apart form swinging in the
plane of the rod. The rod is also restricted from rotating.
Preferably, as shown in the cut-out, the joining of the rod is made
by way of a simple linkage with a hole 57 extending trough ends 58
of the rod 56, the ends being supported in a U-shaped brace 59
having holes 60 extending through the branches of the U, and a bolt
61 or split extending through the holes 60 in the branches of the
brace 59 and through the hole 57 in the ends 58 of the rod 56.
[0095] The fourth holder ensures firstly that the lowest one of the
suspended first holders does not have the possibility to start
swinging because of the natural vibrations as mentioned above.
Secondly the fourth holder ensures that the lower one of the
suspended first holders does not have the possibility to rotate,
when the nacelle rotates. This is an object in order to ensure that
the part of the cables extending from the lower one of the first
holders and to the stationary part of the wind turbine, which in
the embodiment shown is a second type of holder (see FIG. 21) do
not rotate. The rotation of the cables being suspended between the
nacelle and the lower one of the first type of holder will be the
only part of the cables that is being rotated. Because the rotation
of this part of the cables takes place over a rather long distance,
then the overall twisting of the cables is limited. If however the
twisting of the cables took place only along the limited part
extending between the lower one of the first type of holder and the
stationary part, then the twisting of the cables would be
excessive. This risk is eliminated by using the fourth type of
holder, which is also evident from the figure.
[0096] It is however important that the lower one of the first type
of holders can be raised and lowered in relation to the stationary
part, because when the cables being suspended are twisted during
the rotation of the nacelle, then the distance between the nacelle
and the lower one of the first type of holders will decrease, and
the lower holder will raise. Because of the linkage between the
lower holder and the stationary part is made by a rigid rod then,
when the lower holder is raised the lower holder will also be
pulled a little towards the side of the stationary structure onto
which the fourth type of holder is secured. The distance that the
lower suspended holder is pulled sideways is, however, very limited
depending on the distance that the lower suspended holder is
raised.
[0097] FIG. 24 shows a suspension that is secured to an
intermediate floor in the wind turbine tower. Intermediate floors
are provided in the tower and at least a floor is provided just
below the nacelle. The suspension is by means of the bolts
extending form the inner rod and outwardly secured to a triangular
brace. The triangular brace is secured to the floor or to other
fixed parts of the stationary part of the wind turbine, in this
case the wind turbine tower. By securing one or more of the
suspensions to intermediate floors or other fixed parts of the
stationary part then it will be possible to install the cables
before transporting the wind turbine to the location of erection
without the risk of the cables being detached or in any other way
being damaged during transportation. In the figure a brace is used
because the suspension extends through a hole in the floor and the
brace maintains the suspension in the center of the hole which is
also the position of the suspension when the wind turbine is
erected. However, other means than a brace may be used for
maintaining the suspension in place in relation to the floor or
other fixed part of the stationary part of the wind turbine.
[0098] When the cables are supported in the suspension and the
suspension is temporarily secured to a fixed part of the stationary
part then it is possible to install all cables before erecting the
wind turbine. This makes it a lot easier to install the cables
because the cables are rather heavy. If the cables are to be
installed after the wind turbine has been erected, then it is
necessary to first lift one end of the cables all the way from the
bottom of the wind turbine to the nacelle, to attach the end of the
cables at the appropriate place, and then afterwards suspending the
suspensions and thereafter the cables to the suspensions.
Especially the last step of suspending the cables in the
suspensions is very difficult because the suspension must take
place in the center of the tower, the center being difficult to
reach.
[0099] It will be possible voluntarily to use the holders described
solely or in combination. Each of the holders server their own
purpose in suspending the cables form the nacelle to the bottom of
the tower, and the more of the four holders that are used the more
controlled will the suspension of the cables be. However, due to
the rather limited space within the wind turbine tower it is also
of interest to limit the numbers of holders used. In the above the
invention is mostly described with reference to suspension of
cables. However, it will be possible to suspend other like items,
such as hoses, as example hydraulic hoses, or ropes etc.
[0100] The invention being thus described, it will be obvious that
the same may be varied in many ways. Such variations are not to be
regarded as a departure from the spirit and scope of the invention,
and all such modifications as would be obvious to one skilled in
the art are intended to be included within the scope of the
following claims.
* * * * *