MOVABLE COVER STRUCTURES

This invention relates to movable cover structures, particularly although not exclusively for use with swimming pools.

It is known to provide a swimming pool with a cover which can act as a load-supporting floor or platform when the pool is not required for use.

Thus US-A-4598506 describes a platform which is movable between a raised position in which it is stored overhead, and a lowered position at which it covers the pool and provides a floor space for a recreation or party room. The platform is raised and lowered on vertical guide posts. US-A-3114153 describes a cover for an outdoor swimming pool which is slidable horizontally between a protective position at which it extends over the pool and a retracted position at which it is clear of the pool. The cover constitutes a substantial raised structure and has downwardly projecting wheels which run on tracks beneath the cover. An external winch is provided for movement of the cover. When drained of water, the covered swimming pool can be used as a secure shelter and access hatches are provided in the cover.

An object of the present invention is to provide a movable platform which can be used conveniently for movement horizontally between a supportive covering position and a retracted out of the way position. According to a first aspect of the present invention therefore there is provided a movable cover structure comprising a platform which is mounted so as to be displaceable horizontally along a path between first and second positions at which the platform respectively covers a fixed ground area and is retracted clear of such area, the platform providing an exposed supportive cover surface in said first position,

characterised in that the movement of the platform along the said path is effected by interengagement of at least one drive track and at least one drive rotatable element connected to power driving means for drivable rotation thereof.

With this arrangement, movement of the platform between the respective positions can be effected in a particularly convenient manner and also the platform can be readily integrated into its surroundings without undue obtrusion whereby efficient and convenient use can be made of the platform, the fixed ground area and the surroundings thereof in both the covering and retracted positions.

In particular, the fixed ground area may incorporate a swimming pool whereby in the covering position the platform can conveniently be used as a floor or ground surface to accommodate persons seated or standing or engaging in sporting or recreational activities, and in both the retracted and covering positions the platform need not unduly restrict usage of areas adjoining the swimming pool.

It is however to be understood that the invention is not intended to be restricted to use with swimming pools.

The movable cover structure of the invention may be used for any suitable purpose in any suitable context. Thus for example the fixed ground area may constitute a ground surface outside a garage or other storage area whereby the platform may be used for moving a vehicle supported on the platform in and/or out of the storage area.

The platform may constitute a single panel or multiple panels movable together or separately.

For guidance of movement of the platform along the said path there may be provided interengageable guide track and guide rotatable elements.

The guide rotatable elements and guide tracks may be provided at opposite long edges of a rectangular said platform. The guide rotatable elements may be on the platform movable therewith, the guide tracks being fixed alongside the platform.

The guide rotatable elements may be wheels and the guide tracks may comprise channel or angle-section members.

The guide rotatable elements may be mounted on the platform so as to be rotatable about horizontal or substantially horizontal axes and may project outwardly beyond the respective platform periphery.

The interengagement of the guide rotatable elements and guide tracks may thus occur transversely displaced beyond the platform periphery.

Preferably the guide tracks extend substantially wholly along the fixed ground area and also beyond such area to achieve guidance throughout substantially all of the length of the platform substantially throughout the entire movement between the said positions. The (or each) drive rotatable element may also be a said guide rotatable element, or may be a separate rotatable element. The (or each) drive track may also be a said guide track or may be a separate track.

The power driving means may comprise any suitable kind of motor or actuator particularly a hydraulic motor. An electric motor may be used and this may be a low voltage motor powered from mains supply via a transformer or other voltage reducing device. By way of example, the motor may be a 24 v motor drawing say 30 amps whereby the current at mains voltage may be only 3 amps. For safety purposes operation of the motor may require simultaneous actuation of two switches which may be press buttons or the like

which require continuous application of pressure for actuation. Thus, there may be three buttons: a forward movement button, a reverse movement button, and an additional button, whereby the user has to press and hold one of the forward and reverse movement buttons simultaneously with the additional button. These buttons may be provided on a wall mounted control box or the like. Other arrangements are also possible.

The motor or other driving means may be mounted on the platform so as to be movable therewith. In this case drive may be applied directly to one or more drive rotatable elements on the platform. Alternatively or additionally the driving means may be mounted alongside the platform so as to be fixed relative to the ground area. Drive may be transmitted to the platform via one or more drive rotatable elements mounted alongside the platform for engagement therewith e.g. via a said drive track, such as a toothed drive track, on the platform. In one embodiment there are drive rotatable elements mounted alongside the platform at opposite sides thereof drivably linked with each other e.g. by a drive shaft extending transversely to the direction of movement of the platform. With this arrangement there may be drive tracks mounted on the platform at opposite sides thereof and these may run alongside and separate to the aforesaid guide tracks along the length of the platform. The drive tracks may extend at least substantially along the entire length of the platform. In one embodiment the drive tracks extend beyond the platform at a forward end thereof for engagement with the drive rotatable elements beyond the platform when the platform is in the said first (cover) position.

The cover structure may be used within premises or outdoors. Most

preferably, in order to ensure unobtrusive arrangement of the platform in the retracted state, the platform slides beneath a floor or ground surface to be at least partially and preferably substantially wholly concealed therebeneath on movement to the retracted position. Thus, in accordance with a second aspect of the present invention there is provided a movable cover structure comprising a platform which is mounted so as to be displaceable horizontally along a path between first and second positions at which the platform respectively covers a fixed ground area and is retracted clear of such area, the platform providing an exposed supportive cover surface in said first position, characterised in that a floor structure with a space therebeneath is provided adjacent to the said fixed ground area, the movement of the platform along the said path is guided by guide means whereby in the said second position the platform is stowed in said space beneath the said floor structure, and power means is provided for powering said movement. The guide means may comprise interengageable guide tracks and guide rotatable elements and the power means may comprise power driving means connected to at least one drive rotatable element drivably interposed between the platform and the ground area, and this may drivably engage a respective drive track.

The platform may have further guide wheels, e.g. at opposite sides at the leading end region of the platform, which are rotatable about upright or vertical axes for rolling engagement transversely with upright surfaces of the tracks. These further guide wheels help prevent transverse distortion or lozenging of the platform.

The second aspect of the invention may be combined with the first aspect of the invention and/or may incorporate any or all of the subsidiary features of the first

aspect of the invention, as described above, as appropriate.

With either aspect of the invention, preferably appropriate controls are provided for remote operation and preferably also suitable security and/or safety devices are provided to protect against unauthorised operation and/or unsafe operation. In the latter respect, for example, sensors and associated control devices, such as infrared or other directed beam system, may be provided to detect presence of a person on the platform and/or in the fixed ground area, e.g. in the swimming pool where provided, to prevent and/or give warning of movement of the platform.

In the interests of safety, one or more sensors may be provided whereby operation of the power driving means, at least in the direction towards the cover position, is prevented if the, or any one, sensor is actuated indicating the presence of an obstructing body in the area to be covered e.g., as appropriate, the presence of a person in the swimming pool. There may also be a timer whereby on power up and/or after initiating or completing retraction of the platform from the covered area movement of the platform to the cover position cannot be initiated until a short time has elapsed, say 30 seconds, during which the status of any sensor is checked. This may be signalled by an indicator on a control box, e.g. a green light which is only illuminated at the end of the timed period and no activated sensor is detected.

With regard to the sensor or sensors these may take any suitable form. By way of example there may be any one or more, preferably, as appropriate, all of: a transverse sensor whereby a detector beam runs along a leading edge of the platform, transversely to the direction of movement of the platform so as to be interrupted by an obstructing body at the leading edge; one or more longitudinal sensors whereby a detector beam runs forwardly from a leading edge of the platform in the direction of

movement of the platform, preferably at each side edge of the platform so as to be interrupted by any obstructing body at the (or each) such edge; and, in the case of a swimming pool, a motion detector within the water of the pool so as to be actuated by any detected movement of the water e.g. by flow within the body of water or by rise and fall of the water surface.

The platform may be coplanar with some or all adjacent surfaces in one or both positions or it may be displaced above or below one or more such adjacent surfaces. With the second aspect of the invention, the arrangement may be such that the upper surface of the platform is coplanar with the upper surface of the adjacent said floor structure in the covering position whereby a ramped or curved guide path is provided to displace the platform downwardly into the said space when the platform is retracted. Alternatively, the platform may be stepped down from the upper surface of the floor structure in the covering position whereby no downward displacement may be necessary on retraction. The invention will now be described further by way of example only and with reference to the accompanying drawings in which: Figure 1 is a diagrammatic perspective view showing one form of a movable cover structure according to the invention in situ, in an open position; Figure 2 is a plan view of the arrangement of Figure 1 in a closed position; Figure 3 is a transverse vertical section on the line III-III of Figure 2;

Figure 4 is an enlarged side edge view of a front end region of the cover structure of Figure 1 ; and Figures 5, 6 are enlarged plan and end edge views of the front end region.

Referring to Figures 1-3, these show a building structure 1 with upright

walls 2 and a roof (not shown) defining an enclosure around a ground area containing a large excavated cavity 4 for a swimming pool.

The swimming pool cavity 4 is sealed, finished with an appropriate surface, such as tiles, and is connected to water supply, purification and drainage in the usual way (not shown). The internal side and end walls of the cavity are vertical and the internal bottom surface of the cavity is inclined as shown, whereby the cavity side walls have inclined bottom edges and the end walls are of different height.

The cavity 4 is rectangular in plan and is bounded beyond its two long sides and a bottom end by coplanar horizontal flat floor surfaces 5. One of said upright walls 2a of the building structure 1 runs parallel and adjacent to the opposite front end of the cavity 4. This wall 2a may be an outer wall of the building structure or it may be an internal wall dividing the structure 1 into separate rooms or enclosures. The wall 2a is provided with a slot-shaped aperture 21 at its lower periphery. As shown in Figure 4, a horizontal flat floor surface 6 is provided by the top surface of a floor or ground structure having upper panelling suspended on transverse bearers 7 above a lower support surface 8 with a narrow free space 9 therebetween. The top surface 6 of the floor structure is displaced above the other coplanar floor surfaces 5. The free space 9 is rectangular. It is contiguous with the adjacent end of the cavity 4 and generally level with the coplanar floor spaces 5 and is slightly larger than the rectangular plan of the cavity 4. This floor surface 6 may be within a room or enclosure of the building structure 1 separated by the wall 2a, or it may be an external floor or ground surface.

The opposite long vertical side walls of the cavity 4 terminate at their top edges level with the adjacent floor surfaces 5. Along the inner surfaces of such walls

there are inset respective square section channels 10 extending longitudinally horizontally slightly below the top surfaces of such walls.

The vertical bottom end wall of the cavity 4 also terminates at its top edge level with the floor surface 5. The top edge of the vertical front end wall of the cavity terminates below such surfaces 5 level with the lower surface 8.

The channels 10 contain channel members 11 which define guide tracks. The channel members 11 run along the entire length of the vertical side walls of the cavity 4 and extend continuously beyond the side walls at the front end into the free space 9 for a length slightly greater than the length of the side walls. The channel members 11 are fixed in positions within this free space 9.

Within the region of the space 9 there is a recess 12 set into the lower surface 8 close to the front end of the cavity 4 extending transversely across such surface 8. Within this recess there are toothed wheels 13 mounted on opposite ends of an axle 14 so as to be rotatable therewith. The axle 14 is rotatably mounted within the recess 12 so as to extend longitudinally thereof with the toothed wheels 13 respectively close to the inner sides of the two channels and projecting partially upwardly beyond the surface 8.

The axle is drivably connected to twin hydraulic motors 12a mounted within the recess 12 mounted on opposite ends of the axle 14, such motors being linked by hydraulic conduits to a controllable hydraulic power source (not shown) mounted at a convenient position within the building.

A cover platform 15 is provided which is substantially equal in size and shape to the rectangular plan of the cavity 4. This platform 15 comprises wood panelling 16 or the like supported on a metal framework of peripheral elongate members 17 and

transverse bearers 18.

Along opposite long sides of the platform 15 the respective elongate members 17 have wheels 19 rotatably mounted on horizontal axes projecting transversely outwardly from the platform 15. These wheels 19 are smooth surfaced guide wheels. Also along the long sides of the platform 15 there are respective toothed racks 20 inwardly of the guide wheels 19 and parallel to the long sides of the platform 15, the teeth of the racks 20 being directed downwardly and being aligned with the toothed wheels 13. The racks 20 extend throughout the entire length of the platform 15.

The platform 15 can fit over the cavity in a cover position, with the guide wheels 19 within the guide tracks 11 in the side walls. In this position, at the said front end the toothed racks 20 are within the floor space 9 and engage the toothed wheels 13, and the opposite end of the platform 15 abuts the inner surface of the respective vertical end wall of the cavity 4 or, if desired, enters a receiving channel in such wall. The top surface of the platform 15 is coplanar and coextensive with the bounding floor surface 5.

A control unit (not shown) is provided for controlling supply of hydraulic pressure from the source to the hydraulic motor 12a. By operation of the motor 12a the platform 15 can be moved between the covering position described above and a stowed position in which the platform is retracted wholly clear of the swimming pool cavity through the aperture 21 and into the floor structure space 9, the depth and other dimensions of such space 9 being sufficient to accommodate the platform 15 in its entirety.

Thus, when it is desired to use the swimming pool, the control unit is operated e.g. by a wall mounted electrical control to cause the toothed wheels 13 to be driven

in engagement with the toothed racks 20 to retract the platform wholly into the inner space 9 of the floor structure.

When the swimming pool is not required for use, the control unit can be operated to drive the toothed wheels 13 to move the platform 15 out of the inner space 9 of the floor structure to cover completely the swimming pool. In this covered position the platform 15 is coplanar with the floor surfaces 5 at the two long sides and the bottom end of the pool but is stepped down relative to the top surface 6 of the floor structure. The platform 15 then provides a floor surface which can be used by persons. Appropriate covers and seals may be provided to ensure that there are no undesirable gaps around the platform 15 and the open end of the free space 9 of the floor structure as appropriate in both positions of the platform 15.

Sensors are provided (not shown) to detect the presence of persons on the platform 15 when it is over the swimming pool, and within the swimming pool when the platform 15 is retracted, and also at the end edge of the platform 15 remote from the floor structure space 9, to ensure that the platform 15 cannot be moved when a person is standing on the platform 15, and to ensure that a person cannot be trapped in the pool or against the end of the platform 15. For example a system using infrared beams across the pool cavity 4 above the water level in the pool may be used to detect the presence of persons in the pool.

It is of course to be understood that the invention is not intended to be restricted to the details of the above embodiment, which are described by way of example only.