Patent Description:
Pool cover systems are known. There are pool cover systems wherein the mechanism for winding and unwinding the pool cover is positioned outside the water, and there are pool cover systems wherein the mechanism for winding and unwinding the pool cover are positioned underwater. The latter known underwater pool cover mechanisms use a stainless-steel tube inside the swimming pool as base for winding and unwinding the slats which cover the swimming pool when unwound.

The function of the cover is to cover the swimming pool when it is not in use. It protects the water from evaporation and loss of water as well as insulation to limit heat loss from the water. Another function of the cover is to avoid accidental access to the swimming pool for people, especially young children which could lead to drowning or other injury.

There are several types of cover systems. Most common type is a cover system where a roll of slats is mounted inside the swimming pool under the water level. The activation of the cover system is done by a motor which can be installed outside or inside the swimming pool. The motor is connected to and rotates a cylindrical-shaped element. For easy reading the cylindrical-shaped element is in the present application called "tube".

The tube needs to rotate. Therefore, a bearing or support system is provided on both ends of the tube, called the motor side and the opposite motor side or the bearing side.

A know mechanism to rotate the tube is a mechanism with a tube motor. This simplifies the mechanism to drive the pool cover. The tube motor is positioned inside the tube and is sealed and protected against water infiltration, and a motor shaft is extending outside the tube. When installed, the motor shaft is supported in a fixed position in a holder which is firmly fixed or attached to the side walls of the swimming pool. When the motor is rotating, an outer arrangement of the motor is rotating around the fixed motor shaft and because the tube is connected with the outer arrangement, the tube is rotating around the fixed motor axis.

The motor can rotate in two directions causing the tube to rotate in two directions. When the slats are connected to the tube, the rotation of the motor unwinds and winds the slats respectively off and on the tube. The size and power of the motor can be adapted according to the needs of the system. A known cover drive system uses for example a tube motor powered by 24V DC.

A power cable is connected to the motor at the side of the motor shaft. The power cable is guided from the inside of the swimming pool to the outside. Outside the swimming pool the cable is connected to a connection box which on its turn is connected by another cable to a pool cover controller.

There are several known methods to bring one end of the power cable outside the swimming pool while avoiding any contact between the slats and the cable during rotation of the cover mechanism. Any contact may damage the motor cable. In one known arrangement a cable duct is provided which is mounted against the side walls of the swimming pool. In another known arrangement a wall duct is provided which is installed inside the wall of the swimming pool, connects the inside with the outside of the swimming pool and guides the motor cable.

The power of the chosen motor is dependent on the size of the cover corresponding to the size of the swimming pool and the size of the slats. The motor must be able to overcome the buoyancy or force from the water on the air-filled slats, especially during the opening of the cover.

The slats are connected the tube. A known arrangement to connect the slats to the tube is by using straps. The straps are fixed at one end to the tube and at the other end to the first slat. The fixation of the straps on the tube is done by using screws and plugs. A number of straps are evenly spaced along the length of the tube. The fixation of the straps to the first slat is done by making slots or holes in the first slat and to loop the strap through the slot of hole in the first slat. This known method of connecting the first slat to the tube has a number of problems. The installer need to be cautious when making the slotted holes in the first slat to make sure that it will be aligned with the fixation point of the strap at the other end to the tube. If the slotted holes are not aligned with the fixation points on the tube, then the straps will be wound under an angle when the cover is opened. Further, not aligned fixation might also result in uneven tension between the different straps when pulling on the slats before winding the slats on the tube.

Known pool cover mechanisms use tubes which are made of stainless steel. The stainless-steel tube must be of the specific grade <NUM>, because the tube is permanently installed in the swimming pool wherein the water may be treated with chlorination. A problem however when using stainless steel tubes is that these tubes are very heavy and difficult to carry and handle. Such tubes require at least <NUM> persons for the installation. Also, the installation of a cover mechanism with a stainless-steel tube is rather complex and requires multiple parts such as metal parts, sealings and different kinds of fixations in order to fix the tube to the side walls of the swimming pool.

Another problem of the stainless-steel tubes is that such tubes need to have a length corresponding to the width of the swimming pool. Most common widths of swimming pools are between <NUM> and <NUM>. This causes the need for special transport to transport the stainless-steel tube from the manufacturer to the customer. Furthermore, the length of the stainless-steel tube is dependent on the final width of the swimming pool, causing that the stainless-steel tube can only be ordered when the final width of the swimming pool is known. This in combination with the fact that the lead time is rather long causes another problem for the installer. On top of that may the width of the swimming pool be varying over the height of the swimming pool causing that measuring the correct width of the swimming pool at the installation height of the tube is cumbersome for the installer which may results in mistakes. And, if a mistake is made then the ordered tube might be too short or will not fit within the width of the swimming pool, which might result in losses for the installer and delays of the installation.

Further, the supports for holding the tube must be very well aligned and accurately positioned on the pool walls. As the pool walls are not always perfectly parallel, it's time consuming for the installer to make the proper alignment. And, to position the supports accurately, corresponding mounting holes must be made to make sure that both centres of the supports are aligned. Improper installation or misalignment may result in excessive wear of several components including motor, slats, guides, bearing surfaces etc..

Other known pool cover mechanisms use tubes outside the swimming pool to wind and unwind the cover.

The installation of the pool cover mechanism is often one of the toughest tasks for the installer. The cover is one of the last items which needs to be installed before filling the pool with water. However, certain installation requirements must be taken into account from the very beginning of the pool construction. From an installer perspective, a lot of time is spent on the installation of the pool cover mechanism because of the complexity and because of the strict requirements for alignment and positioning for smooth operation.

Next to the installation, the pool cover mechanism may also need maintenance or repairing. In known pool cover mechanism, maintenance or repairing of the tube motor is possible but it is very cumbersome. The installed tube must be disassembled from the supports to be able to access the tube motor and drainage of swimming pool is mostly needed. Known pool cover mechanisms of the prior art are for example described in <CIT>, <CIT>, <CIT> and <CIT>.

It is an aim of the present invention to provide a pool cover mechanism which overcomes at least some of the above mentioned problems.

This aim is achieved according to the invention with a pool cover mechanism according to claim <NUM> for winding and unwinding slats over a pool, the pool cover mechanism comprising a tube for connecting with the slats, a tube motor assembly for rotating the tube wherein the tube motor assembly is connected to the tube at a first end and wherein the tube motor assembly comprises a tube motor and a non-rotating motor end when the tube motor is rotating, a first holder for receiving the non-rotating motor end of the tube motor assembly, an outer shaft bearing assembly connected to the second end of the tube wherein the outer shaft bearing assembly is configured to allow rotation of the tube when the tube motor is rotating, a second holder for receiving the outer shaft bearing assembly, wherein the outer shaft bearing assembly and the second holder are configured such that at least part of the outer shaft bearing end can rotate in the second holder when the tube is tilted compared to the position of the tube wherein the motor end is in the first holder and wherein the outer shaft bearing assembly comprises a first group of elements and a second group of elements, wherein the first group of elements and the second group of elements are configured such that the first group of elements can do a sliding movement relative to the second group of elements in the axial direction of the tube.

This pool cover mechanism provides multiple advantages. The installer can position one end of the tube in the holder and can subsequently rotate the other side of the tube to the other holder while the first end remains in the first holder. Further, when maintenance or repair is needed, the installer can remove one end of the tube from the holder, tilt the tube while the other end is rotating in the holder such that the tube motor is accessible without removing the tube from the other holder. This arrangement has also the advantage that when the outer shaft bearing assembly is received in the second holder, the tube can be moved in axial direction of the tube relative to the second holder. This allow to position at the opposite side the tube motor assembly on the exact position in the first holder. Furthermore, the relative sliding movement functionality combined with the tilting functionality have together the advantage that the tube motor can be tilted above the water level of the pool and slid over the side wall of the pool for easy access.

According to the invention, the outer shaft bearing assembly comprises a ball joint and a ball joint housing, wherein the ball joint can rotate in the ball joint housing when the ball joint housing is received in the second holder and the tube is tilted compared to the position of the tube wherein the motor end is in the first holder.

This arrangement with a ball joint and a ball joint housing has the advantage that the outer shaft bearing assembly can be easily mounted in the second holder and that the ball joint has rotational freedom inside the ball joint holder and thus also in the second holder.

According to the invention, the outer shaft bearing assembly comprises an outer shaft bearing connected to the second end of the tube. The outer shaft bearing connected to the outer shaft has the advantage that the outer shaft bearing assembly is supporting the tube very well.

Further according to the invention, the outer shaft bearing has a central opening, the ball joint has a shaft portion, and the central opening and the ball joint are configured such that the outer shaft bearing can slide in the axial direction over the shaft portion.

This arrangement where the outer shaft bearing, and thus also the tube connected to the outer shaft bearing and the tube motor assembly, can slide together over the shaft portion of the ball joint, has the advantage that easy installation by a single person is possible. This arrangement also allows to have some deviations on the tube length compared to the calculated optimal length dependent on the exact width of the swimming pool. Further, by having the combination of the freedom of rotation by the ball joint and the sliding outer shaft bearing over the shaft portion of the ball joint, the tube motor assembly can be tilted up to the edge of the pool above the water level, allowing easy disassembly and assembly of a replacement tube motor.

In an embodiment of the invention, the outer bearing assembly further comprises a stopper and the stopper is configured such that the stopper limits the sliding of the outer shaft bearing over the shaft portion.

The stopper ensures that that the outer bearing remains on the shaft portions.

In an embodiment of the invention, the tube is a single tube.

A mechanism with a single tube can be advantageous in specific situation.

In an embodiment of the invention, the first holder is identical to the second holder.

This is advantage during installation and manufacturing as less different parts are needed.

In an embodiment of the invention, the first holder and the second holder are not identical.

This arrangement may be advantageous in specific situations.

In an embodiment of the invention, the outer shaft bearing assembly and the second holder are configured such that the at least part of the outer shaft bearing assembly can rotate in the second holder between <NUM> and <NUM>° when the tube is tilted between <NUM> and <NUM>° compared to the position of the tube wherein the motor end is in the first holder.

This has the advantage that the tube can be tilted high enough to bring the tube motor above the water level.

In an embodiment of the invention, the tube comprises at least two outer tubes and at least one inner tube, wherein the inner tube is configured to have an outer profile which corresponds to the inner profile of the outer tube such that the inner tube can slide into the outer tubes and such that the inner tube is rotating when the outer tube is rotating.

This pool cover mechanism has the advantage that one set of two outer tubes and one inner tube can be used for a range of widths of the swimming pool. The same tube can be installed at different heights even if the width of the swimming pool is changing over the height of the pool wall. This pool cover mechanism makes the installation of the tube much easier. In an embodiment of the invention, the outer tube has a cylindrical shaped outer profile.

This is advantageous because the slats of the cover are wound on the outer surface of the outer tube such that any protruding elements will have a negative impact on the winding of the slats and might deform or damage the slats.

In an embodiment of the invention, the inner profile of the outer tube comprises at least one recess area and the outer profile of the inner tube comprises at least one protrusion.

This arrangements enables proper engagement with allows power transmission between the outer and inner tube.

In an embodiment of the invention, the at least two outer tubes are fixed with respect to the at least one inner tube such that the at least two outer tubes and the at least one inner tube fixed towards each other have a fixed length.

This arrangement has the advantage that when the desired length of the tube is known during installation, the length of the two outer tubes and the inner tube can be adjusted and fixed. This makes installation more easy.

In an embodiment of the invention, the at least two outer tubes are fixed to the at least one inner tube by at least one screw positioned in the at least one protrusion.

This arrangement has the advantage that it is easy to execute.

In an embodiment of the invention, the inner profile of the outer tube and the outer profile of the inner tube are configured such that there is a minimal clearance between the inner profile of the outer tube and the outer profile of the inner tube.

The clearance has the advantage that backlash is avoided.

In an embodiment of the invention, the inner profile comprises three recessed areas and the outer profile comprises three protrusions.

This arrangement has the advantage that forces can be spread over the circumference of the profiles.

In an embodiment of the invention, the tube further comprises a strap link assembled on the inner tube, wherein the strap link has an outer profile with a cylindrical shape and with a diameter corresponding to the diameter of the outer cylindrical surface of the outer tube.

This arrangement has the advantage that a strap can be connected to the inner profile in the same way as a strap is connected to the outer profile such that the same forces are applied on the first slat.

A further embodiment not forming part of the present invention as claimed describes a pool cover mechanism for winding and unwinding a number of connected slats over a pool, the pool cover mechanism comprising a tube for connecting with the slats, a tube motor assembly for rotating the tube wherein the tube motor assembly is connected to the tube at a first end and wherein the tube motor assembly comprises a tube motor and a non-rotating motor end when the tube motor is rotating, a first holder for receiving the non-rotating motor end of the tube motor assembly, an outer shaft bearing assembly connected to the second end of the tube wherein the outer shaft bearing assembly is configured to allow rotation of the tube when the tube motor is rotating, a second holder for receiving the outer shaft bearing assembly, and at least one strap connected to the tube, characterized in that the pool cover mechanism further comprises at least one slat connector for connecting the at least one strap to the first slat of the number of connected slats, wherein the at least one slat connector comprises a buckle having two leg portions and being configured to connect with the strap and a C-shaped tube having a slit over the whole length of the C-shaped tube for sliding over a part of the slat and having a slot in the C-shaped tube opposite to the slit for receiving the buckle, wherein the slot is configured such that the two leg portions of the buckle are anchored inside the C-shaped tube when the buckle is connected to the strap.

This pool cover mechanism has the advantage that no slots or holes has to be made in the first slat to connect the slats with the tube. The C-shaped slat connector fits to all kind of slats by simply sliding the slat connector over the first slat.

In an embodiment, the strap comprises a loop and the buckle is connected with the loop by arranging a part of the buckle in the loop while the legs of the buckle are arranged in the C-shaped tube.

This arrangement has the advantage that the strap can be connected to the slat without making any holes or slots in the slat and without the need to use extra fixation elements.

In an embodiment, the slit is narrower at the ends of the C-shaped tube compared to the middle of the C-shaped tube.

This arrangement allows to have a width at the sides which is optimized to slide over the slats and to have at the same time a width in the middle to assemble the strap and the buckle.

The terms so used are interchangeable under appropriate circumstances and the embodiments of the invention described herein can operate in other orientations than described or illustrated herein.

The term "comprising", used in the claims, should not be interpreted as being restricted to the elements or steps listed thereafter; it does not exclude other elements or steps. It needs to be interpreted as specifying the presence of the stated features, integers, steps or components as referred to, but does not preclude the presence or addition of one or more other features, integers, steps or components, or groups thereof. Thus, the scope of the expression "a device comprising A and B" should not be limited to devices consisting only of components A and B, rather with respect to the present invention, the only enumerated components of the device are A and B, and further the claim should be interpreted as including equivalents of those components.

<FIG> illustrates a pool cover system according to an embodiment of the present invention. The pool cover system has a tube <NUM>, a tube motor assembly <NUM>, an outer shaft bearing assembly <NUM>, straps <NUM>, slats <NUM>, buckles <NUM>, slat connectors <NUM> and two holders <NUM>.

As illustrated in <FIG>, the tube <NUM> has in the embodiment of <FIG> two <NUM> outer tubes <NUM> and <NUM> inner tube <NUM>. In an alternative embodiment the tube <NUM> can be a single tube. Or, in still another embodiment the tube <NUM> can have more than two outer tubes <NUM> and more than one inner tubes <NUM>. The tube <NUM> can be made at a length corresponding to the width of a swimming pool. In embodiments with more than one outer tube <NUM> or more than one inner tube <NUM>, the length of each outer tube <NUM> and each inner tube <NUM> can be different.

In the embodiment of <FIG>, the two outer tubes <NUM> and the inner tube <NUM> are assembled together to meet the required length to be mounted in a swimming pool. The length of the tube <NUM> can be adjusted to correspond to the width needed for the swimming pool. With a single tube set of two outer tubes <NUM> and an inner tube <NUM> a range of lengths can be covered depending on the length of the outer tubes <NUM> and the length of the inner tube <NUM>. In this embodiment, the minimum length of the tube <NUM> is determined by the length of the two outer tubes <NUM> at a position wherein both outer tubes <NUM> are adjacent to each other and wherein the inner tube <NUM> is completely covered by both outer tubes <NUM>. In this assembling position, half of the inner tube <NUM> is preferably covered by the first outer tube <NUM> and the other half of the inner tube <NUM> is preferably covered by the second outer tube <NUM>. Still in the embodiment of <FIG>, the maximum length of the tube <NUM> is determined by the length of both outer tubes <NUM> and the exposed length of the inner tube <NUM>. The maximum length is two times the length of the outer tube <NUM> plus the length of the inner tube <NUM> minus the minimum inserted portion of the inner tube <NUM> inside the outer tubes <NUM>. In a preferred embodiment of the present invention, the minimum inserted portion of the inner tube <NUM> is at each side approximately <NUM>. Between the minimum length and the maximum length of the tube <NUM>, all tube lengths are possible. This structure of the tube <NUM> provides a lot of advantages. The installer does not need to wait until the swimming pool is finished to order the tube <NUM> because an indication of the required length of the tube is sufficient to order. Once the pool is finished, the tube <NUM> can be adjusted to the needed length by sliding the outer tubes <NUM> over the inner tube <NUM> until the desired length is reached and by fixing subsequently the outer tubes <NUM> with the inner tube <NUM> at this desired length. Small deviations of the width of the swimming pool compared to the technical drawings of the project have no longer an impact on the installation or timing. For embodiments wherein the tube <NUM> is installed underwater, the outer tube <NUM> and the inner tube <NUM> are preferably made of stainless steel <NUM> or glass fibre reinforced vinyl ester. In alternative embodiments, other materials may be used.

As illustrated in <FIG>, the outer tubes <NUM> and inner tube <NUM> are fixed together in axial direction by means of screws <NUM> and plugs <NUM>. In an alternative embodiment of the present invention, fixation of the outer tubes <NUM> and the inner tube <NUM> can be performed by means of bolts, bolts and screws in combination with hollow wall anchors, split pens or any other fixation means which does not protrude outside the outer cylindrical surface <NUM> of the outer tube <NUM>.

The cylindrical surface <NUM> of the outer tube <NUM> should remain free from any protruding elements because the slats <NUM> of the cover are wound on this outer surface <NUM>. Any protruding elements will have a negative impact on the winding of the slats <NUM> and might deform or damage the slats <NUM>. For this reason, the pre-drilled holes in the outer tubes <NUM> to fix the outer tube <NUM> with the inner tube <NUM> are countersunk holes in which the head of the fixation element is recessed.

The outer tubes <NUM> have holes <NUM> (shown in Section B-B in <FIG>), which are used to connect an end of the straps <NUM> to the outer tubes <NUM>. The straps <NUM> are at the other end connected to the slats <NUM>. In an embodiment of the present invention, the straps <NUM> can have one or more holes to insert a plug <NUM> to fix a strap <NUM> to an outer tube1. In an alternative embodiment, a different method can be applied to fix a strap <NUM> to an outer tubes <NUM>. Each outer tube <NUM> has several holes <NUM> for connecting straps <NUM>. Preferably the holes <NUM> are equally spaced over the length of an outer tube1. Depending on the actual adjusted length of the tube <NUM> more or less holes <NUM> of the outer tubes <NUM> can be used.

In an embodiment of the present invention, in case the tube <NUM> is not set to the minimum length, a strap link <NUM> is provided as illustrated on <FIG> and <FIG>. The strap link <NUM> is slid over the inner tube <NUM> and has the same profile as the outer tube <NUM>. Preferably the strap link <NUM> is positioned and fixed in the middle of the inner tube <NUM> and allows the fixation of a strap <NUM> in the middle of the tube <NUM>. The strap link <NUM> may also have a pre-drilled hole for fixing the strap <NUM>, similar as the holes <NUM> in the outer tube <NUM>. The width of the strap link <NUM> must be at least equal to the width of a strap <NUM>. In another embodiment, the width of the strap link <NUM> is larger than the width of a strap <NUM> in order to be more tolerant towards misalignments between the location of the strap connection <NUM> with the slats <NUM> and the location of the strap link <NUM> on the inner tube <NUM>. The strap link <NUM> may be fixed by means of screws <NUM> to the inner tube <NUM>. In an embodiment, the strap link <NUM> is connected to the inner tube <NUM> such that the hole in the strap link <NUM> for fixing a strap <NUM> is aligned in axial direction with the holes <NUM> in the outer tubes <NUM> for fixing the straps <NUM>. This alignment of the holes has the advantage that straps <NUM>, which have the same length, also have the same amount of tension when pulling the slats <NUM>.

<FIG> and <FIG>, and <FIG> and <FIG> illustrate the tube motor assembly <NUM>. The tube motor assembly comprises a tube motor <NUM>, a front motor flange <NUM>, a rear motor flange <NUM>, a motor shaft <NUM>, a backlash rubber <NUM> and a motor pin <NUM>. The tube motor <NUM> is inserted in one of the outer tubes <NUM>. The tube motor <NUM> is fixed in axial direction with the outer tube <NUM> by means of screws <NUM> (shown in <FIG>) which are screwed in the direction perpendicular to the axial direction. Instead of screws <NUM> other fixation means can be applied to hold the tube motor <NUM> in position inside the outer tube <NUM>.

The front flange <NUM> and the rear flange <NUM> are assembled on the tube motor <NUM>. Both flanges <NUM>, <NUM> have an outer profile which corresponds to the inner profile of the outer tube <NUM> such that the front flange <NUM> and the rear flange <NUM> can slide into the outer tube <NUM> and such that the front flange <NUM> and the rear flange <NUM> rotate the outer tube <NUM> when the tube motor <NUM> is rotating. In the embodiment of <FIG>, the outer profile of the front flange <NUM> and the rear flange <NUM> is corresponding to the outside profile of the inner tube <NUM>. In an alternative embodiment, the profile of the front flange <NUM> and the rear flange <NUM> assembled on the tube motor <NUM> can have a different shape in order to fit the outer tube <NUM> and to transfer the power from the tube motor <NUM> to the tube <NUM>.

<FIG> shows a cross section of the front flange <NUM> according to an embodiment of the present invention wherein the front flange has an outer profile with three recesses <NUM> for matching and engaging with protrusions of the outer tube <NUM>. <FIG> shows a view on the rear flange <NUM>. In this embodiment, the rear flange has similar recesses <NUM> to match and engage with protrusions of the outer tube <NUM>.

The front flange <NUM> comprises also a cover portion <NUM>, which covers the side of the tube when the tube motor <NUM> is full inserted inside the outer tube <NUM>. Once the tube motor <NUM> is fully inserted in the outer tube <NUM>, then the tube motor <NUM> can be fixed in axial direction in the outer tube, by inserting the screws <NUM> through the pre-drilled holes in the outer tube <NUM> and screwing the screws <NUM> in the front flange <NUM> of the tube motor <NUM>.

At least part of the motor shaft <NUM> is positioned outside the outer tube <NUM> when the tube motor <NUM> is assembled in the outer tube. The backlash rubber <NUM> is provided on the motor shaft <NUM> and the motor pin <NUM> is inserted in the backlash rubber <NUM> and in a hole <NUM> of the motor shaft <NUM> as illustrated in <FIG>. The motor pin <NUM> holds the backlash rubber <NUM> in position at the motor shaft <NUM>. The motor shaft <NUM> further comprises a hole <NUM>, through which the motor cable is guided. The backlash rubber <NUM> is assembled on the motor shaft <NUM> as such that the side holes <NUM> are aligned with the hole <NUM> on the motor shaft. Once the holes of the backlash rubber <NUM> and the hole <NUM> on the motor shaft <NUM> are aligned, then the motor pin <NUM> can be inserted in the holes of the backlash rubber and through the hole <NUM> in the motor shaft.

The tube motor assembly <NUM> is, when mounted in a pool, fixed in a holder <NUM> which is first fixed to a pool wall. The motor pin <NUM> is used to fix the motor shaft <NUM> in a holder bottom <NUM> of the holder <NUM>. The backlash rubber <NUM> dampens the reaction forces when the motor is activated. When the tube motor <NUM> is rotating, the motor shaft <NUM> remains fixed and the motor body with the front flange <NUM> and the rear flange <NUM> assembled to the motor is rotating. When the tube motor assembly <NUM> is positioned in the holder bottom <NUM>, a holder top <NUM> is snap fit in the holder bottom <NUM> which fixes the motor shaft <NUM> and the backlash rubber <NUM> in axial direction in the holder bottom <NUM>.

The holder bottom <NUM> is screwed in the sidewalls of a swimming pool by means of screws <NUM> and plugs <NUM>. In an alternative embodiment bolts and anchors can be used to fix the holder bottom <NUM> to the sidewall of the swimming pool. In yet another embodiment the holder bottom <NUM> can be mounted and fixed on a hanging plate.

<FIG> and <FIG> and <FIG> and <FIG> illustrate the outer shaft bearing assembly <NUM>. In the embodiment of <FIG>, the outer shaft bearing assembly <NUM> comprises an outer shaft bearing <NUM>, a ball joint <NUM>, a ball joint housing <NUM>, a washer <NUM>, a retaining washer <NUM> and a bolt <NUM>. The outer shaft bearing <NUM> is inserted in the outer tube <NUM>. The outer shaft bearing <NUM> is fixed in axial direction to the outer tube <NUM> by means of screws <NUM> (shown in <FIG>) which are screwed in the direction perpendicular to the axial direction. Instead of screws <NUM> other fixation means can be applied to hold the outer shaft bearing <NUM> in position inside the outer tube <NUM>. In the embodiment of <FIG>, the outer shaft bearing <NUM> has an outer a profile which corresponds to the inner profile of the outer tube <NUM> such that the outer shaft bearing <NUM> can slide into the outer tube <NUM> and such that the outer tube <NUM> rotates the outer shaft bearing <NUM> when the motor is rotating.

The outer shaft bearing <NUM> can rotate freely on a shaft portion <NUM> of the ball joint <NUM>. The ball joint <NUM> further comprises a spherical portion <NUM>. Before the outer shaft bearing <NUM> is slid in the outer tube <NUM>, the shaft portion <NUM> of the ball joint <NUM> is inserted through the hole in the ball joint housing <NUM>. In the next step the shaft portion <NUM> of the ball joint assembly <NUM> is inserted in the central hole <NUM> of the outer shaft bearing <NUM>. Then, the washer <NUM> is fixed to the shaft portion <NUM> of the ball joint <NUM> by using the retaining washer <NUM> and the bolt <NUM>. In alternative embodiments, washer <NUM> may be fixed to the shaft <NUM> in another manner known in the art. The outer shaft bearing <NUM> also has recessed areas <NUM> to match and engage with protrusions of the outer tube <NUM>. In this structure, the outer shaft bearing <NUM> can not only rotate around the shaft portion <NUM>, the outer shaft bearing <NUM> can also move over the shaft portion <NUM> in the axial direction. The washer <NUM> ensures that the shaft portion <NUM> remains in the outer shaft bearing <NUM>. As the outer shaft bearing can move axially on the shaft portion <NUM>, also the tube mechanism assembly <NUM> can move axially on the shaft portion <NUM> of the ball joint <NUM> until the outer shaft bearing <NUM> hits the washer <NUM> which is screwed at the shaft end of the shaft portion <NUM> of the ball joint <NUM> with the screw <NUM> and retaining washer <NUM>. In alternative embodiments other stopper known in the art may be used.

The outer shaft bearing assembly <NUM> is mounted in a second holder which is in the embodiment of <FIG> the same as the first holder <NUM> of the tube motor assembly <NUM>. In an alternative embodiment are the first holder for the tube motor assembly <NUM> and the second holder for the outer shaft bearing assembly <NUM> different holders. The ball joint <NUM> with the ball joint housing <NUM> is positioned in the holder bottom <NUM>. Once positioned is the holder top <NUM> snap fit in the holder bottom <NUM>. By snap fitting the holder top <NUM> in the holder bottom <NUM> are the ball joint <NUM> and the ball joint housing <NUM> fixed in axial direction in the holder bottom <NUM>. The shape of the ball joint <NUM> allows in this mounted position rotational freedom of the ball joint <NUM> inside the bottom holder <NUM> such that the tube <NUM> can be tilted while the ball joint <NUM> and the ball joint housing <NUM> are mounted in the second holder <NUM>. The tube <NUM> with the tube motor assembly <NUM> connected to it on the one side and the outer shaft bearing <NUM> connected to it on the other side is together called the tube mechanism assembly <NUM>. Because the outer shaft bearing <NUM> can freely rotate and move with respect to the shaft portion <NUM> of the ball joint <NUM>, can the tube mechanism assembly <NUM> rotate and move in axial direction over the shaft portion <NUM> of the ball joint <NUM>. Further, with the functionality that the ball joint <NUM> can rotate in the holder <NUM> when mounted, when the tube motor assembly <NUM> is detached from the first holder <NUM>, the tube <NUM> can be tilted while the ball joint <NUM> remains in the second holder <NUM>. The angle of rotational freedom towards the nominal axis defined by the axis of the tube when assembled in the holders <NUM> on both walls of the swimming pool, ranges from <NUM> to at least <NUM>°. This embodiment of the present invention is illustrated in <FIG>. In the perspective view of <FIG>, the outer shaft bearing assembly <NUM> is mounted in the second holder <NUM>. <FIG> illustrates that with the ball joint <NUM> fixed in the holder <NUM>, the ball joint <NUM> can rotate in the ball joint housing <NUM> which remains fixed in the holder <NUM>. The tube <NUM> with the tube motor assembly <NUM> can tilt <NUM>° in all directions. This rotational freedom has many advantages. The rotational freedom allows the installer to install the cover mechanism by a single person. One can first mount the outer shaft bearing assembly <NUM> in the holder bottom <NUM>. Once the ball joint <NUM> and the ball joint housing <NUM> is fixed with the holder top <NUM>, the tube <NUM> can be rotated to mount at the other side of the tube <NUM> the tube motor assembly <NUM> in the first holder <NUM>.

As shown in <FIG>, in the alternative embodiment wherein the tube <NUM> is a single tube <NUM>, for example the outer tube <NUM>, the tube motor assembly <NUM> and the outer shaft bearing assembly <NUM> are connected to both sides of the single tube. The single tube <NUM> can in the same way be tilted in all directions while the outer shaft bearing assembly <NUM> remains in the second holder <NUM>.

<FIG> and <FIG> show the cross section of respectively the inner tube <NUM> and the outer tube <NUM> according to an embodiment of the present invention. The cross sections of the inner tube <NUM> and the outer tube <NUM> illustrate that the outer profile of the inner tube <NUM> matches and engages with the inner profile of the outer tube <NUM>. The matching of the outer profile of the inner tube <NUM> with the inner profile of the outer tube <NUM> enables proper engagement which allows power transmission between the outer <NUM> and the inner tube <NUM>. Between the inner profile and the outer profile is a minimal clearance in rotational direction to avoid backlash.

In the embodiment of <FIG> and <FIG> consist the outer profile of the inner tube <NUM> of three recessed areas <NUM> in the outer cylindrical circumference <NUM>. The three recessed areas <NUM> are separated from each other under an angel of <NUM>°. The three recessed areas <NUM> of the inner tube <NUM> match and engage with three protrusions <NUM> at the inner profile of the outer tube <NUM>. The outside profile of the outer tube <NUM> has a cylindrical shape <NUM>. The three protrusions <NUM> are equally spaced over the inside of the outer tube <NUM>.

<FIG> further illustrates the outer tube <NUM> according to an embodiment of the present invention. The main drawing in <FIG> is a cross sectional view in longitudinal direction. In this view is indicated where a number of cross section views in radial direction are taken which are shown in separate section views. Section C-C shows the cross section of the outer tube <NUM> at the location indicated in the longitudinal view and which corresponds to the location where the tube motor assembly <NUM> or the outer shaft bearing <NUM> will be fixed by screws <NUM>. The Section C-C shows that in this embodiment three countersunk holes <NUM> are provided in each protrusion <NUM> of the outer tube <NUM>. Section B-B shows the cross section of the outer tube <NUM> at the location indicated in the longitudinal view and which corresponds to the location where a strap <NUM> is connected by a plug <NUM> which is press fit in the hole <NUM>. Section D-D shows a further cross section of the outer tube <NUM> at the location indicated in the longitudinal view and which corresponds to the location where the inner tube <NUM> is connected with the outer tube <NUM> by inserting plugs <NUM> and screws <NUM> in the countersunk holes <NUM>.

<FIG> illustrate the assembly of a tube <NUM> according to an embodiment of the present invention. <FIG> illustrates the first step of assembling a part of the inner tube <NUM> in the outer tube <NUM>. The inner tube <NUM> is inserted and slid in the first outer tube <NUM>. Based on the width of the swimming pool and depending on the length of the tubes, it can be calculated how much the inner tube <NUM> needs to be inserted in the outer tube <NUM>. The distance D is the distance of the inner tube <NUM> which needs to be inserted in the first outer tube <NUM>. For the tube set with pool width range from <NUM>,<NUM> to <NUM>,<NUM>, the distance D is calculated as follows D= (<NUM>-W)/<NUM> whereby W is equal to the width of the pool. For the tube set with pool width range from <NUM>,<NUM> to <NUM>,<NUM>, the distance D is calculated as follows D= (<NUM>-W)/<NUM> whereby W is equal to the width of the pool.

<FIG> illustrate to connect the assembly of <FIG> to a second outer tube <NUM>. The inner tube <NUM> is now inserted in the second outer tube <NUM>. Based on the width of the swimming pool and depending on the length of the tubes, it can be calculate how much the inner tube needs to be inserted in the outer tube. The distance D is calculated in the same way as for the insertion in the first outer tube1.

<FIG> illustrates the fixing of the outer tube <NUM> with the inner tube <NUM>. Once the inner tube <NUM> is in the correct position in relation with the outer tubes <NUM>, one has to drill holes in the inner tube <NUM> which correspond with the pre-drilled countersunk holes in the outer tube <NUM>. Plugs <NUM> and screws <NUM> are inserted in the pre-drilled countersunk holes in the outer tube <NUM> and in the holes drilled in assembly in the outer tube <NUM>. Once the plugs <NUM> and screws <NUM> are inserted, the screws <NUM> are tightened and as such the plugs <NUM> are pulled against the inner wall of the inner tube <NUM>.

<FIG> and <FIG> show two perspective views of a pool cover mechanism according to an embodiment of the present invention in two positions, once in an operational position and once in an installation or maintenance position. In the perspective view of <FIG>, the first holder and the tube motor assembly <NUM> is shown. In the perspective view of <FIG>, the second holder and the outer shaft bearing assembly <NUM> is shown. In the operational position, the tube motor assembly <NUM> is in the first holder <NUM>. In the installation or maintenance position, the tube motor assembly <NUM> is dismounted from the first holder and the tube <NUM> is tilted while the outer shaft bearing assembly <NUM> is still in the second holder. Furthermore, as the tube mechanism assembly <NUM> can move in axial direction over the shaft portion <NUM> of the ball joint <NUM>, the tube mechanism can also be moved in the direction of the arrow. This functionality allows the installer to get easily access to the tube motor when needed, for example when the tube motor <NUM> needs to be disassembled from or assembled in the tube <NUM> for repair or maintenance purposes. It also allows easy installation by one person. This functionality also allows for deviations on the tube length compared to the measured value of the width of the swimming pool.

The tube <NUM> is tilted up to a position where the tube motor side is above the water level of the pool and the tube mechanism assembly <NUM> is displaced along the shaft portion <NUM> of the ball joint <NUM>. In this way, the end of tube <NUM> with the tube motor assembly <NUM> is beyond the edge <NUM> of the pool <NUM>.

<FIG> illustrate the steps for installing the outer shaft bearing assembly <NUM> in the second holder <NUM> which is fixed to a side wall of a swimming pool. The outer shaft bearing assembly <NUM>, connected to tube <NUM>, including the ball joint <NUM> is the first side to be mounted when installing a pool cover mechanism. The outer shaft bearing assembly <NUM> is mounted in the holder bottom <NUM> of the holder <NUM> by a drop-in assembly. The holder bottom <NUM> comprises a vertical slot that receives the ball joint housing <NUM>. The vertical slot in the holder bottom <NUM> is extending horizontally in the direction away from the wall. Therefore, as illustrated in <FIG>, in a next step the ball joint holder <NUM> and the ball joint are pulled in the direction of the arrow such that the ball joint holder <NUM> moves in the horizontal slot. In this position, the ball joint holder is fixed in the vertical direction by the slot. In a next step, as illustrated in <FIG>, once the ball joint <NUM> and the ball joint housing <NUM> are in the correct position in the horizontal slot inside the holder bottom <NUM>, the holder top <NUM> can be inserted and snap fit with the holder bottom <NUM>. In this way, the holder top <NUM> closes also the axial freedom of the ball joint holder <NUM> in the second holder <NUM> such that the ball joint holder <NUM> is now at a fixed position in the second holder <NUM>. To give feedback to the installer that the holder top <NUM> is installed correctly, the holder top <NUM> is configured to provide a click sound when the holder top <NUM> is in the correct position in the holder bottom <NUM>. This is illustrated in <FIG>.

<FIG> illustrate the steps for installing the tube motor assembly <NUM> in the first holder <NUM> which is fixed to a side wall of a swimming pool. The outer shaft bearing assembly <NUM> at the opposite side of the tube <NUM> is at that moment already mounted in the second holder. As illustrated in <FIG>, firstly the motor cable <NUM> needs to be connected and inserted in the cable guide or hole. Then, the tube mechanism assembly <NUM>, including the tube <NUM>, the tube motor assembly <NUM> and the outer shaft bearing <NUM>, can move over the shaft <NUM> of the ball joint <NUM> while the ball joint <NUM> can tilt. By this movement, the tube motor assembly <NUM> with the backlash rubber <NUM> and the motor pin <NUM> can be dropped in the holder bottom <NUM>. The holder bottom <NUM> has a vertical slot wherein the motor pin makes a vertical movement when the tube motor assembly <NUM> is dropped in the holder. The vertical slot is extending in a horizontal slot. Therefore, as illustrated in <FIG>, in a next step the backlash rubber <NUM> and the motor <NUM> are pulled in the direction of the arrow on <FIG> such that the motor pin <NUM> moves into the horizontal slot. In a next step, as illustrated in <FIG>, once the backlash rubber <NUM> and the motor pin <NUM> are in place in the horizontal slot of the holder bottom <NUM>, the holder top <NUM> is inserted and snap fit with the holder bottom <NUM>. If the holder top <NUM> is snap fit in the correct position a click sound is generated by the holder <NUM>. This is illustrated in <FIG>. The sound provides a confirmation to the installer that holder is correctly closed.

<FIG> illustrate how the straps <NUM> are connected to the slats <NUM> according to an embodiment not forming part of the invention as claimed. The straps <NUM> are connected to the slats <NUM> by means of a slat connector <NUM> and a buckle <NUM> (shown in <FIG>). The slat connector <NUM> is a C-shaped tube <NUM>, which can slide over the typical hooks <NUM> of the slats <NUM>. The hooks <NUM> can have different shapes. By having the C-shape, the C-shape tube <NUM> can be used for all kind of slats <NUM> with different designs of the hooks <NUM>. The buckle <NUM> comprises a main area and two legs <NUM>. The main area is used to hook a loop <NUM> of the strap. The two legs <NUM> are located at each side of the main part of the buckle <NUM> and are used to hook inside the slat connector <NUM>.

The buckle <NUM> is inserted in the slat connector <NUM> from the slit side <NUM> (shown on <FIG>) of the C-shaped tube <NUM>. One end of the buckle <NUM> will be pulled through a slot <NUM> in the slat connector which is at the opposite side of the slit <NUM>. The buckle <NUM> will be hold in position inside the slat connector <NUM> by means of the legs <NUM> of the buckle <NUM>, which remain hooked inside the slat connector.

Claim 1:
A pool cover mechanism for winding and unwinding slats over a pool, the pool cover mechanism comprising
- a tube (<NUM>) for connecting with the slats (<NUM>);
- a tube motor assembly (<NUM>) for rotating the tube (<NUM>) wherein the tube motor assembly (<NUM>) is connected to the tube (<NUM>) at a first end and wherein the tube motor assembly (<NUM>) comprises a tube motor (<NUM>) and a non-rotating motor end (<NUM>, <NUM>) when the tube motor (<NUM>) is rotating;
- a first holder (<NUM>) for receiving the non-rotating motor end (<NUM>, <NUM>) of the tube motor assembly (<NUM>);
- an outer shaft bearing assembly (<NUM>) connected to the second end of the tube (<NUM>) wherein the outer shaft bearing assembly (<NUM>) is configured to allow rotation of the tube (<NUM>) when the tube motor (<NUM>) is rotating;
- a second holder (<NUM>) for receiving the outer shaft bearing assembly (<NUM>);
wherein the outer shaft bearing assembly (<NUM>) and the second holder (<NUM>) are configured such that at least part of the outer shaft bearing assembly (<NUM>) can rotate in the second holder (<NUM>) when the tube (<NUM>) is tilted compared to the position of the tube wherein the motor end (<NUM>, <NUM>) is in the first holder (<NUM>), characterized in that the outer shaft bearing assembly (<NUM>) comprises a first group of elements (<NUM>) and a second group of elements (<NUM>, <NUM>), wherein the first group of elements and the second group of elements are configured such that the first group of elements can do a sliding movement relative to the second group of elements in the axial direction of the tube (<NUM>), wherein the outer shaft bearing assembly (<NUM>) comprises a ball joint (<NUM>) and a ball joint housing (<NUM>), wherein the ball joint (<NUM>) can rotate in the ball joint housing (<NUM>) when the ball joint housing (<NUM>) is received in the second holder (<NUM>) and the tube (<NUM>) is tilted compared to the position of the tube wherein the motor end is in the first holder, wherein the outer shaft bearing assembly (<NUM>) comprises an outer shaft bearing (<NUM>) connected to the second end of the tube (<NUM>) wherein the outer shaft bearing (<NUM>) has a central opening, wherein the ball joint (<NUM>) has a shaft portion (<NUM>), and wherein the central opening and the ball joint (<NUM>) are configured such that the outer shaft bearing <NUM> can slide in the axial direction over the shaft portion (<NUM>).