PRESSURE-DISTRIBUTING ELEMENTS

The present invention relates to a telescopic grandstand, for placing on a surface, comprising at least one first platform and at least one second platform, wherein the first platform is displaceable with respect to the second platform, between a retracted position, in which the first platform is situated virtually completely underneath the second platform, and an extended position, in which the first platform extends virtually completely in front of the second platform, and comprising at least one pressure-distributing element to distribute the load of the first platform over the surface.

More specifically, but not limiting, this telescopic grandstand is suitable for placing on a sports floor as surface.

Such telescopic grandstands, which can be placed on a sports floor, are typically configured to be arranged in a sports venue, where, depending on the use of the venue, the floor has to be cleared for sports activities or a (seated) grandstand is desired which takes up a part of the floor in order to accommodate (seated) spectators. In their retracted state, these grandstands may be very compact, with several platforms being arranged one above the other. In the extended state, the platforms are then arranged in a stepped manner with respect to each other. These platforms may optionally be provided with folding seats. A problem of telescopic grandstands for placing on a sports floor is the fact that such a sports floor is particularly susceptible to damage. Such a sports floor is typically able to absorb high loads for a short time, but is less well able to absorb loads for a longer period of time. In case of an excessive load at the location of the wheels of such a telescopic grandstand, a sports floor may become permanently damaged. In order to prevent or limit this, such a sports floor is typically reinforced at the location of such a telescopic grandstand, which does, however, not benefit the resilient properties of such a sports floor. Such a reinforcement is therefore prevented or limited as much as possible.

It is also known to provide such a grandstand with pressure-distributing elements in order to better distribute the load of this grandstand and the spectators seated thereon over this sports floor, as a result of which it is damaged less easily. Such pressure- distributing elements are already known in the form of pressure-distributing shoes or pressure-distributing plates.

In the most popular embodiments, pressure-distributing shoes or blocks are arranged next to the wheels, thus making it possible to roll platforms of such a grandstand on a surface. In the retracted state and while retracting or extending the platforms, these pressure-distributing blocks are situated at a certain intermediate distance from the surface. These pressure-distributing blocks are sprung by means of mechanical springs or gas springs, so that these can sink under the weight of spectators taking a seat on the grandstand in order to be supported on the surface. Examples of such solutions have been described and illustrated in FR 2 746 433 Al, US 3,222,827, DE 24 56 697 Al and DE 298 13 512 Ul.

A significant drawback of these solutions is the fact that the load of the grandstand is only distributed if the spectators sitting thereon have a sufficiently large weight. However, such sports grandstands often remain in an extended state for a prolonged period, for example when several matches are being played during the course of a weekend. During such periods in which these grandstands remain in an extended state, the sports floor often becomes damaged as a result of the dead weight of this grandstand.

A further drawback is the fact that such pressure-distributing blocks can only distribute the load over a limited surface area, as a result of which the sports floor still has to absorb high local loads.

WO 2006/076772 Al already describes an alternative solution, in which the load of the grandstand can also be distributed over the surface during prolonged extended states. In this case, the pressure-distributing blocks can also sink under the weight of spectators, but they can also be manually or automatically pulled up or lowered as desired, in an active manner. However, in this case, the lowering of these pressure- distributing blocks requires an intentional active action. In this case, the load is also still distributed over a limited surface area, as a result of which the sports floor still has to absorb high local loads.

With the telescopic grandstand as described and illustrated in DE 32 18 579 Al, the wheels by means of which the platforms are displaceable are rolled onto pressure- distributing plates, which are lowered for this purpose, when extending the grandstand, just before the completely extended state thereof. When retracting the platforms again, the wheels are rolled off these pressure-distributing plates again and these pressure-distributing plates are pulled up again. In this way, the load of this grandstand is always distributed over the pressure-distributing plates in the extended state of the grandstand, without this distribution depending on the weight of spectators who are seated on this grandstand and without requiring a separate action for this. However, the pressure plates have to be provided with relatively large openings in order to enable the wheels to extend through these so as to be able to retract and extend the grandstand. The lifting and lowering of the pressure plates also requires a relatively complicated system.

The object of the present invention is to provide such a telescopic grandstand which is provided with a simple system by means of which an improved distribution of the load of the grandstand over the surface can be achieved in all circumstances.

This object of the invention is achieved by providing a telescopic grandstand, for placing on a surface, such as a sports floor, comprising at least one first platform and at least one second platform, wherein the first platform is displaceable with respect to the second platform, between a retracted position, in which the first platform is situated virtually completely underneath the second platform, and an extended position, in which the first platform extends virtually completely in front of the second platform, and comprising at least one pressure-distributing element to distribute the load of the first platform over the surface, wherein the pressure- distributing element is configured as a guide element for guiding the sliding movement of the first platform over the surface. Because the pressure-distributing element is now configured as a guide element for guiding the sliding movement of the first platform over the surface, this pressure- distributing element no longer has to be lifted up or held up in order to be able to move the first platform. Now, the pressure-distributing element can always remain positioned at the same distance on or just above the surface. This pressure- distributing element can thus remain lowered at all times in order to both guide this sliding movement and to distribute the load of the first platform over the surface, both when the grandstand is empty and when spectators are seated thereon. In this way, the load of this grandstand is always distributed over the pressure-distributing plates, without this distribution depending on the weight of spectators who are seated on this grandstand and without requiring a separate action for this.

Due to the fact that the pressure-distributing element no longer has to be lifted up or held up and lowered, this pressure-distributing element can be incorporated in the grandstand using a simpler mechanism than is the case with the prior art. Such a simpler mechanism may also be made more lightweight which again benefits the load of the surface.

Also, this pressure-distributing element no longer has to be able to move up and down between running wheels, so that this can be designed over a larger surface area than any prior-art pressure-distributing element in order to rest on the surface. The larger this surface, the better the distribution of the load over the surface.

In addition, using such a pressure-distributing element as a guide element, running wheels no longer have to be provided in order to make the first platform rollable over the surface. By means of this guide element, this first platform may be made displaceable only with respect to this surface. By omitting such running wheels, large loads on a small contact surface between such running wheels and this surface are also prevented. Preferably, at least one such pressure-distributing element is provided on at least both sides of the first platform, so that this first platform remains supported on both sides during the sliding movement. Furthermore preferably, all platforms which are displaceable with respect to the second platform are provided (on both sides) with at least one such pressure- distributing element. Thus, when the telescopic grandstand comprises several first platforms which are each displaceable with respect to the second platform between a retracted position, in which each first platform is situated virtually completely underneath the second platform, and an extended position, in which each first platform extends virtually completely in front of the second platform, then each of these first platforms is preferably provided with at least one such pressure- distributing element and still more preferably provided with at least one such pressure-distributing element on either side thereof.

Preferably, a telescopic grandstand according to the present invention also comprises drive means for driving the sliding movement of the first platform, so that this can automatically be extended and/or retracted. These drive means then preferably comprise a push chain. Such a push chain is able to transmit both pulling force and pushing force, by means of which the grandstand can be retracted as well as extended. By means of such a push chain, it is possible to ensure that the load on the surface is reduced compared to other typical drive means, and this in the zone where this surface is either cleared by the grandstand in the retracted state of the grandstand or occupied in the extended state of the grandstand. The fact is that by means of such a push chain, it is possible to ensure that the relatively heavy parts of the drive means are arranged underneath the part of the grandstand which occupies the surface at all times. In this way, it is possible to ensure that the part of the surface which can be cleared by the grandstand is subjected to as little load as possible by these drive means. To this end, this push chain may, for example, be accommodated in the grandstand, as is described in EP 2 345 780 Al, the contents of which are deemed to be incorporated by reference. In this case, the drive means may be provided with one such push chain or they may be provided with several push chains which are arranged distributed along the width of the grandstand and are preferably driven synchronously. In a particular embodiment, the pressure-distributing element of a grandstand according to the present invention is configured as a pressure-distributing plate. In the form of a pressure-distributing plate, such a pressure-distributing element can easily be made strong and lightweight.

In this case, such a pressure-distributing plate preferably comprises a base for supporting the pressure-distributing plate on the surface and two flanges which stand upright on both sides with respect to this base in order to provide optimum guidance of this pressure-distributing plate over the surface. Furthermore, this pressure- distributing plate may also be provided with an upright flange on the front side and the rear side in order to further optimize guidance of the pressure-distributing plate on the surface.

A pressure-distributing element for a grandstand according to the present invention may, more specifically, be made of metal. A said pressure-distributing plate with upright flanges may, more specifically, be formed by means of folding, in which case the upright flanges are folded with respect to the base.

In a particularly preferred embodiment of a telescopic grandstand according to the present invention, viewed in the direction of the sliding movement, a first return wheel is arranged so as to be rotatable, on the front side of the pressure-distributing element and a second return wheel is arranged so as to be rotatable on the rear side of the pressure-distributing element, wherein an endless belt is arranged so as to be rotatable around these return wheels and partly extends between the pressure- distributing element and the surface. By means of such a belt, which is arranged around the return wheels so as to be rotatable, it is possible to limit the friction of the pressure-distributing element over the surface during the sliding movement. In this case, preferably a single belt is provided, but, if desired, it is also possible to arrange several belts next to each other. It is likewise possible to arrange several of said return wheels next to each other for supporting one or several such belts. The return wheels are preferably arranged directly on the said ends of the pressure- distributing element, but, if desired, it is also possible to arrange several successive pressure-distributing elements between both return wheels.

The return wheel on the front side of the pressure-distributing element is preferably arranged virtually at the location of the front side of the first platform. The return wheel on the rear side of the pressure-distributing element is preferably arranged virtually at the location of the rear side of the first platform.

The said return wheels are preferably not driven directly by means of drive means, but only arranged so as to be rotatable, so that they only rotate when this is being caused on account of the sliding movement. With a said telescopic grandstand comprising a pressure plate with upright flanges, the said return wheels can more specifically be arranged between the upright flanges of the pressure-distributing plate and be attached to these upright flanges so as to be rotatable. In order to prevent smaller contact surfaces between the surface and the grandstand, the distance of each return wheel from the surface is preferably greater than the distance of the pressure-distributing element from the surface.

The return wheels are preferably made of plastic in order to minimize friction and wear resulting from this friction.

The said belt is preferably also made from plastic in order to minimize friction and wear resulting from this friction.

Preferably, the return wheels have a smooth running surface. The surface of the belt which faces towards the return wheels is preferably also flat. Alternatively, but less preferably, the running surface of the return wheels may, for example, be provided with teeth with which teeth of the belt can mesh.

The surface of the belt which faces away from the return wheels is preferably flat.

In a particular embodiment, a plastic plate may be arranged between the pressure- distributing element and the belt in order to minimize friction between the various parts and wear of these parts resulting from this friction. Viewed in the direction of the sliding movement, the pressure-distributing element preferably extends over a distance which is at least half, more preferably at least two thirds of and most preferably virtually the corresponding dimension of the first platform. The present invention will now be explained in more detail by means of the following detailed description of a preferred embodiment of a telescopic grandstand according to the present invention. The sole aim of this description is to give illustrative examples and to indicate further advantages and particulars of the present invention and can therefore not be interpreted as a limitation of the area of application of the invention or of the patent rights defined in the claims.

In this detailed description, reference numerals are used to refer to the attached drawings, in which:

- Fig. 1 shows an embodiment of a telescopic grandstand according to the present invention with cut-away platforms viewed in perspective from the front side and from the top;

- Fig. 2 shows the telescopic grandstand from Fig. 1 with cut-away platforms viewed in perspective from the rear side and from the top;

- Fig. 3 shows a part of the telescopic grandstand from Fig. 1, at the location of a pressure-distributing plate thereof, viewed in perspective from the rear side and from the top; - Fig. 4 shows the part of the telescopic grandstand from Fig. 3 viewed in perspective from the left-hand side and from the bottom;

- Fig. 5 shows a part of Fig. 4 at the location of the second return wheel in greater detail;

- Fig. 6 shows the part from Fig. 5 in side view.

The illustrated telescopic grandstand (1) comprises 6 platforms (3, 4, 5), the filling elements of which have not been shown in order to give a clearer image of the structure which is present underneath these telescopic grandstands (1). The platforms (3, 4, 5) are displaceable with respect to each other, so that the grandstand (1) can extend and retract telescopically in a known manner. In Figs. 1 and 2, this grandstand (1) is shown in its extended state. In this extended state, all platforms (3, 4, 5) are arranged next to each other. In the retracted state, all platforms (3, 4, 5) are arranged one above the other.

The front platform (3) is a first platform (3) which is displaceable with respect to every platform (4, 5) situated behind as a second platform, between a retracted position, in which this first platform (3) is situated virtually completely underneath the second platform, and an extended position, in which the first platform (3) extends virtually completely in front of the second platform.

The rear platform (4) is a second platform (4) with respect to which each platform (3, 5) situated in front thereof as a first platform is displaceable between a said retracted position, in which this second platform (4) is situated virtually completely above the first platform, and an extended position, in which the second platform (4) extends virtually completely in front of the first platform.

All intermediate platforms (5) thus serve as a first platform with respect to every platform (4, 5) situated behind and serve as a second platform with respect to every platform (3, 5) situated in front. Each platform (3, 4, 5) comprises the required beams in order to support the filling elements (not shown) and is supported by a support frame (21) with support columns (18), supporting beams (19, 23), reinforcing arms (24) and reinforcing plates (20). This support frame (21) is made from metal.

At the bottom of each support frame (21), a lateral supporting beam (19) is arranged. This lateral supporting beam (19) comprises a U-shaped folded plate (19). A pressure-distributing plate (6) is attached to this U-shaped folded plate (19) by means of bolts (22). This pressure-distributing plate (6) comprises a base (25) and, on both sides of this base (25), a folded flange (26) which is upright with respect to the base (25). Between these folded flanges (26) a first return wheel (10) is attached to the front side of the pressure-distributing plate (6) so as to be rotatable and a second return wheel (1 1) is attached to the rear side of the pressure-distributing plate (6) so as to be rotatable. To this end, each of these return wheels (10) is rotatable about a rotation shaft (14). Around these return wheels (1 1), an endless belt (12) is arranged so as to be rotatable. In order to tension the endless belt (12), the rotation shaft (14) of the second return wheel (11) is attached to an attachment plate (15) which is provided with slots (16) and is displaceably attachable to the pressure-distributing plate (6) by means of screws (17) through these slots (16). Alternatively, it would also be possible to use other known tensioning systems to tension this endless belt (12). The return wheels (10, 11) and the belt (12) are made of plastic. The running surface of the return wheels (10, 11) is flat and the belt (12) is likewise flat. Between the pressure-distributing plate (6) and the belt (12), a plastic plate (13) is arranged.

By means of the pressure-distributing plates (6) on both sides of each platform (3, 4, 5), the load of this platform (3, 4, 5) is distributed over the surface (2) and the sliding movement of this platform (3, 4, 5) over the surface (2) is guided. The sliding movement of the platforms (3, 4, 5) is driven by drive means (7, 8, 9), which comprise a push chain (7). To this end, a receiving housing (8) for this push chain (7) and a gearbox (9) are arranged at the back of the grandstand (1).