[0001] This invention relates to retractable roofs, and is particularly relevant to large-scale
retractable roofs of the type employed to cover the centre of a stadium such as an
athletics or football stadium.
[0002] Given the cost of building large stadia there has been an interest in recent years
in providing stadia which can be a venue for many different uses, not only simply
for a single sport or type of event. In addition, there has been created a need for
stadia which can be used throughout the year, regardless of weather conditions, and
at any time, day or night. This has produced an increasing need for stadia which have
roofs which can be moved so that a stadium can provide a traditional outdoor venue,
but can still be used under adverse weather conditions and/or when temperatures drop
at night, without affecting the comfort of the users of the stadium.
[0003] In recent time there have been proposed, and, indeed, built, many stadia with such
roofs. There are difficulties, however, in providing such roofs. Firstly, they can
be extremely expensive and difficult to maintain given the support structures required
to ensure rapid and reliable movement of the roof. In addition, the requirement of
such roofs is such that they can increase significantly the overall cost of the stadia,
given that their additional weight introduces additional structural burdens on the
rest of the building. For example, it is usual to use arches, trusses or suchlike
to support the roof across its entire span.
[0004] The present invention seeks to provide a roof which is retractable, but which can
be employed to cover a large area and which has considerably reduced weight in comparison
with known retractable roofs.
[0005] WO-A-8904896 discloses a retractable roof with reflexable roof covering.
[0006] According to the present invention there is provided a system for operating a retractable
roof, the system comprising:
a first support having a first pulley;
a second support positioned opposite to and across from the first support means and
having a second pulley; and
a movable tie member which passes around the first and second pulleys to form an elongate
loop having a crossover point between the supports, characterised in that the roof
has at least two rigid movable roof sections and in that the first roof section is
supported, in use, by the tie member between the first support and the crossover point
and the second roof section is supported, in use, by the tie member between the crossover
point and the second support such that, in use, the roof sections move in opposite
directions when the tie member is moved and characterised in that:
the tie member passes through each support twice to provide resistance to lateral
movement.
[0007] One of the pulleys may be provided with driving means, such as a motor and gearbox,
for moving the tie member and thus operating the roof. The tie member may pass through
each support twice to form a double loop arrangement to provide resistance to lateral
movement. In this double loop arrangement, the tie member may be connected to each
roof section in two places, one of which is a pulley point and the other is a fixed
point, that is clamped to the tie member such that the roof section is caused to move
with the tie member. The first and second roofs sections may, in use, be attached
to the tie member at points equidistant from the cross over point.
[0008] Additional pulleys may be provided on each side of the crossover point between the
support and the connection of the tie member to the roof section for controlling the
path which the tie member takes and thus altering the direction of travel of the roofsections.
If the additional pulleys are placed so as to lower the path of the tie member, then
the direction of travel of the roof section will be made more convex/less concave.
If the additional pulleys are placed so as to raise the path of the tie member, then
the direction of travel of the roof section will be made more concave/less convex.
[0009] The position of the additional pulley may be controlled by, for example, a hydraulic
ram. The ram may also adjust the tension of the tie member so that it is maintained
at a substantially constant value to ensure that undue stresses are not placed on
the system.
[0010] The roof sections may be arranged such that, when they are in the closed position,
they are able to lock with one another to provide additional support to one another
and to provide a rigid roof structure.
[0011] The present invention also provides a retractable roof having one or more systems
for operation thereof, and in which the roof sections may be concave or convex.
[0012] Preferably, the roof is provided with two systems, each having two roof sections
associated therewith, such that a total of four roof sections are provided. The roof
may be provided with an outer section which is fixed in place and on which the retractable
roof is movably mounted on rails. The fixed outer section typically extends over nearly
all of the spectator area within the stadium and usually the fixed section extends
over approximately half the diameter of the roof. Alternatively, certain projects
may require the fixed section to be smaller and thus it may cover only about onc third
of the roof diameter. In this arrangement, the roof sections may be formed from more
than one roof element, such that, in the retracted position, the roof elements are
stacked one on top of another, and, in the extended position, the elements are adjacent
to each other to form a roof section.
[0013] The fixed outer section may be provided with retaining means for preventing the retractable
roof sections from being lifted when in the retracted position, such as by a sudden
updraft of wind. The retaining means preferably comprises a cable which is attached
at one end to the fixed roof section, preferably the underside thereof, or to a ring
beam and at the other end is slidably mounted on the underside of the retractable
roof.
[0014] According to the invention there is also provided a stadium comprising a roof and
system of the type described above. Such a stadium may comprise one or more roofs,
each of which may have one or more corresponding systems.
[0015] Thus the present invention provides a roof which breaks the supporting span of the
roof such that arches, trusses and suchlike are not required.
[0016] An example of the present invention will now be described with reference to the accompanying
drawings, in which:
Figures 1 to 3 are schematic perspective views of a stadium roof employing a system
of the present invention, showing the roof in a fully retracted, a partially closed,
and a fully closed configuration;
Figures 4a and 4b are side views of a system according to the present invention;
Figures 5a and 5b are side views of a further example system according to the present
invention;
Figure 6 is a plan view of a further example system according to the present invention;
Figure 7 is a schematic plan view of a roof which uses two systems of the present
invention; and
Figure 8 is a side elevation view of a stadium having a retractable roof and a roof
retaining means.
[0017] Referring to figure 1, a stadium roof 21 has a peripheral fixed region, and a central
open region 22. In this case the overall shape of the roof 21 is oval as is that of
the open region 22, although this does not have to be the case. The roof and/or the
open region could be elliptical, circular, rectangular or any other shape. Associated
with the roof 1 are two first supports 23 and two second supports 24. Each support
has a movable roof section 25, 26 associated therewith and attached to its respective
support 23, 24 via a tie member 27, which is a steel support cable or similar. Each
support 23, 24, may also provide support for the fixed roof section via support cable
28.
[0018] Each of the movable roof sections 25, 26 can be moved from a retracted position (figure
1) to a fully closed position (figure 3) via an intermediate position (figure 2).
When in a closed position fixing members (not shown) may be moved to connect adjacent
movable roof sections, 25, 26 to provide a rigid roof structure that is water-tight
and which is resistant to up-drafts or down-drafts generated by weather conditions
and conditions within the stadium beneath the roof 21.
[0019] In the example four movable roof sections are provided, although it would be appreciated
that only two may be provided, or that more than four may be provided, just so long
as there is an even number.
[0020] The operation of the supports 23, 24, movable roof sections 25, 26 and tie members
27 will now be described. Referring to figures 4a and 4b a simplified configuration
of a system according to the invention is shown, in which components corresponding
to those in figures 1 to 3 are numbered identically. In this example the movable roof
sections 25, 26 are configured to move through an arc 31. Each movable roof section
25, 26 is attached to the tie member 27, which passes over pulleys (not shown) at
each support 23, 24. The configuration is such that there is a cross-over point 32
in the centre of the system, with each movable roof members 25, 26 being on an opposite
side of the cross over section 32 to the other. In use, movement of the tie member
27 around the pulleys (not shown) on the supports 23, 24 moves the two roof members
25, 26 toward each other and indicated by the arrows, until they are in a closed position
of the type shown in figure 4b. Because the roof sections 25, 26 are positioned equidistant
from the supports 23, 24 with respect to one another, and because they have identical
weight, the tension in the tie member 27 is balanced.
[0021] Figures 5a and 5b show a second example of the invention, in which components corresponding
to those in figures 4a and 4b are numbered identically. In this example the tie member
27 passes around additional points 34, 35 positioned below the pulleys on the supports
23, 24. This produces a movement in which the roof sections 25, 26 pass through a
curve 33 having a direction of curvature opposite to that of curve 31 shown in figures
4a and 4b.
[0022] The simplified structure shown in figures 4a to 5b may be adequate in many circumstances,
but there will be situations in which additional support is required and in which
it is necessary to improve the system in respect of resistance to lateral forces applied
to the movable roof sections 25, 26 due to high winds, etc. In such cases, a double
loop arrangement of the type shown in figures 6 and 7 may be employed. In this arrangement
four pulley points are provided at each support member 23, 24, with the tie member
27 passing through each pulley point once in a looped configuration. The tie member
27 is movably connected at one point 1, 1a on each of the movable roof sections 26
and is fixed at a second point 5, 5a on each of the roof sections 25.
[0023] The arrangement of Figure 7, in which components corresponding to those in previous
figure are numbered identically, clearly shows the direction in that the tie member
27 is arranged around the various pulleys and fixed points. It is not important at
which point the tie member 27 starts but in this example, points 1, 1a are designated
as fixed points on respective roof sections 26. From this fixed point, the tie member
27 follows the path indicated by the ascending numbers until it returns to its starting
point 1, 1a. The points labelled 5, 5a on the opposing roof sections 25 are also fixed
points.
[0024] A roof retaining means 34 can be seen in Figure 8 and is provided with a cable 35
which may be a steel cable of the sort used in the tie member. The cable 35 is attached
at one end to the underside of the roof sections 25,26 by a slide mechanism (not shown)
similar to that employed as a door latch. The other end of the retaining means is
attached to a ring beam 36 mounted on the peripheral fixed roof section. The retaining
means is constructed such that the cable is in tension when the roof sections 25,26
are in the fully retracted position.
1. A system for operating a retractable roof (1), the system comprising:
a first support (23) having a first pulley;
a second support (24) positioned opposite to and across from the first support (23)
means and having a second pulley; and
a movable tie member (27) which passes around the first and second pulleys to form
an elongate loop having a crossover point (32) between the supports, characterised in that the roof has at least two rigid movable roof sections (25,26) and in that the first roof section is supported, in use, by the tie member between the first
support and the crossover point and the second roof section is supported, in use,
by the tie member between the crossover point and the second support such that, in
use, the roof sections move in opposite directions when the tie member is moved and
characterised in that:
the tie member (27) passes through each support twice (23, 24) to provide resistance
to lateral movement.
2. A system according to claim 1, wherein the tie member (27) doubles back on itself
at the first support (23).
3. A system according to claim 1 or 2, wherein the first and second roof sections (25,
26) are, in use, equidistant from the crossover point (32).
4. A system according to any one of the preceding claims, further comprising at least
one additional pulley through which the tie member (27) passes.
5. A retractable roof having one or more systems according to any one of the preceding
claims.
6. A roof according to claim 5, wherein the roof sections (25, 26) are convex.
7. A roof (21) according to claim 5, wherein the roof sections (25, 26) are concave.
8. A roof according to any one of claims 5 to 7, wherein two systems according to any
one of claims 1 to 5 are provided and having two roof sections (25, 26) for each system.
9. A roof according to any one of claims 5 to 8, wherein one or more roof sections (25,
26) are formed from a number of roof elements such that, in the retracted position,
the roof elements are stacked one on top of another, and, in the extended position,
the elements are adjacent to each other to form a roof section.
10. A roof according to any one of claims 5 to 9, further comprises retention means (35)
for preventing the retractable roof sections from being lifted when in the retracted
position.
11. A roof according to claim 10, wherein the retention means (35) comprises a cable (35)
which is attached at one end to the fixed roof section and at the other end is slidably
mounted on the underside of the retractable roof.
12. A stadium having a retractable roof (1) according to any one of claims 5 to 11.
13. A stadium according to claim 12, wherein only a portion of the roof (1) is retractable
and further comprising additional tie members (28) between the supports (23, 24) and
the non retractable portion of the roof.
1. System zum Betreiben eines zurückziehbaren Daches (1), wobei das System umfaßt:
einen ersten Träger (23) mit einer ersten Rolle;
einen zweiten Träger (24), der gegenüberliegend und quer zum ersten Träger (23) angeordnet
ist und eine zweite Rolle hat; und
ein bewegliches Verbindungselement (27), das um die ersten und zweiten Rollen führt,
um eine längliche Schleife mit einem Kreuzungspunkt (32) zwischen den Trägern auszubilden,
dadurch gekennzeichnet, daß das Dach wenigstens zwei feste, bewegliche Dachabschnitte (25, 26) hat und daß der
erste Dachabschnitt im Gebrauch von dem Verbindungselement zwischen dem ersten Träger
und dem Kreuzungspunkt getragen wird und der zweite Dachabschnitt im Gebrauch von
dem Verbindungselement zwischen dem Kreuzungspunkt und dem zweiten Träger getragen
wird, derart, daß im Gebrauch die Dachabschnitte sich in entgegengesetzte Richtungen
bewegen, wenn das Verbindungsglied bewegt wird und
dadurch gekennzeichnet ist, daß das Verbindungselement (27) zweimal durch jeden Träger (23, 24) gelangt, um einen
Widerstand gegenüber einer seitlichen Bewegung zu liefern.
2. System nach Anspruch 1, bei welchem das Verbindungselement (27) sich auf sich selbst
umlenkt bei dem ersten Träger (23).
3. System nach Anspruch 1 oder 2, bei welchem die ersten und zweiten Dachabschnitte (25,
26) in Gebrauch gleich von dem Kreuzungspunkt (32) beabstandet sind.
4. System nach einem der vorstehenden Ansprüche, des weiteren umfassend wenigstens eine
zusätzliche Rolle, durch welche das Verbindungselement (27) gelangt.
5. Zurückziehbares Dach mit einem oder mehreren Systemen nach einem der vorstehenden
Ansprüche.
6. Dach nach Anspruch 5, bei welchem die Dachabschnitte (25, 26) konvex sind.
7. Dach (21) nach Anspruch 5, bei welchem die Dachabschnitte (25, 26) konkav sind.
8. Dach nach einem der Ansprüche 5-7, bei welchem zwei Systeme gemäß einem der Ansprüche
1-5 vorgesehen sind und zwei Dachabschnitte (25, 26) für jedes System haben.
9. Dach nach einem der Ansprüche 5-8, bei welchem einer oder mehrere Dachabschnitte (25,
26) aus einer Anzahl an Dachelementen derart gebildet sind, daß in der zurückgezogenen
Stellung die Dachelemente eines oben über das andere gestapelt sind und in der ausgefahrenen
Stellung die Elemente aneinander angrenzen, um einen Dachabschnitt zu bilden.
10. Dach nach einem der Ansprüche 5-9, des weiteren umfassend eine Halteeinrichtung (35)
zum Verhindern, daß die zurückziehbaren Dachabschnitte angehoben werden, wenn sie
sich in der zurückgezogenen Stellung befinden.
11. Dach nach Anspruch 10, bei welchem die Halteeinrichtung (35) ein Kabel (35) umfaßt,
das mit einem Ende an dem festen Dachabschnitt angebracht ist und mit dem anderen
Ende verschiebbar an der Unterseite des zurückziehbaren Daches montiert ist.
12. Stadion mit einem zurückziehbaren Dach (1) nach einem der Ansprüche 5-11.
13. Stadion nach Anspruch 12, bei welchem nur ein Abschnitt des Daches (1) zurückziehbar
ist und des weiteren umfassend zusätzliche Verbindungselemente (28) zwischen den Trägern
(23, 24) und dem nicht-zurückziehbaren Abschnitt des Daches.
1. Système destiné à actionner un toit rétractable (1), le système comprenant :
un premier support (23) comportant une première poulie ;
un second support (24) positionné à l'opposé et en face du premier moyen de support
(23) et comportant une seconde poulie ; et
un élément de traverse mobile (27) qui passe autour des première et seconde poulies
pour former une boucle allongée ayant un point de croisement (32) entre les supports,
caractérisé en ce que le toit comporte au moins deux sections de toit mobiles rigides (25, 26) et en ce que la première section de toit est supportée, lors de l'utilisation, par l'élément de
traverse entre le premier support et le point de croisement et la seconde section
de toit est supportée, lors de l'utilisation, par l'élément de traverse entre le point
de croisement et le second support de sorte que, lors de l'utilisation, les sections
de toit se déplacent dans des directions opposées lorsque l'élément de traverse est
déplacé et caractérisé en ce que :
l'élément de traverse (27) passe à travers chaque support (23, 24) deux fois pour
offrir une résistance au déplacement latéral.
2. Système selon la revendication 1, dans lequel l'élément de traverse (27) fait demi-tour
sur lui-même au niveau du premier support (23).
3. Système selon la revendication 1 ou 2, dans lequel les première et seconde sections
de toit (25, 26) sont, lors de l'utilisation, équidistantes du point de croisement
(32).
4. Système selon l'une quelconque des revendications précédentes, comprenant en outre
au moins une poulie supplémentaire à travers laquelle l'élément de traverse (27) passe.
5. Toit rétractable comportant un ou plusieurs systèmes selon l'une quelconque des revendications
précédentes.
6. Toit selon la revendication 5, dans lequel les sections de toit (25, 26) sont convexes.
7. Toit (21) selon la revendication 5, dans lequel les sections de toit (25, 26) sont
concaves.
8. Toit selon l'une quelconque des revendications 5 à 7, dans lequel deux systèmes selon
l'une quelconque des revendications 1 à 5 sont prévus et comportent deux sections
de toit (25, 26) pour chaque système.
9. Toit selon l'une quelconque des revendications 5 à 8, dans lequel une ou plusieurs
sections de toit (25, 26) sont formées à partir d'un certain nombre d'éléments de
toit de sorte que, dans la position rétractée, les éléments de toit soient empilés
les uns sur les autres, et, dans la position étendue, les éléments soient adjacents
les uns aux autres pour former une section de toit.
10. Toit selon l'une quelconque des revendications 5 à 9, comprenant en outre un moyen
de maintien (35) destiné à empêcher les sections de toit rétractables de se soulever
lorsqu'elles sont dans la position rétractée.
11. Toit selon la revendication 10, dans lequel le moyen de maintien (35) comprend un
câble (35) qui est fixé sur une extrémité à la section de toit fixe et qui, sur l'autre
extrémité, est monté de manière coulissante sur le dessous du toit rétractable.
12. Stade comportant un toit rétractable (1) selon l'une quelconque des revendications
5 à 11.
13. Stade selon la revendication 12, dans lequel seule une partie du toit (1) est rétractable
et comprenant en outre des éléments de traverse (28) supplémentaires entre les supports
(23, 24) et la partie non rétractable du toit.