GB2329831A

GB2329831A - Pool cover system

Info

Publication number: GB2329831A
Application number: GB9720273A
Authority: GB
Inventors: Peter David Jeffery; Rosemary Dawn Jeffery; Ian James Scott Macmath
Original assignee: Individual
Current assignee: Individual
Priority date: 1997-09-25
Filing date: 1997-09-25
Publication date: 1999-04-07
Also published as: GB9720273D0

Abstract

A swimming pool 10 is provided with a pool cover system 1 comprising a pool cover 2 of flexible sheet material, an adjustable tensioning cable 3 extending across the leading edge 4 of the cover 2 and united therewith, and a means 6, 7, 8 for moving the cover relative to the pool. The cover 2 and cable 3 are united by folding back and securing a short length of the leading edge 4 over a flexible tube of PVC and then threading the cable 3 through the tube so formed. Means 20 is provided for varying the tension in the cable 3 so as to cause the leading edge 4 of the cover 2 to be lifted or lowered, relative to the water in the pool. The separate means for causing the cover 2 to move between pool covering and uncovering positions comprise a cable 6 and cable winding means 7, for covering the pool and a pool cover wind-up means 8, for uncovering the pool.

Description

IMPROVEMENTS IN OR RELATING TO POOL COVER SYSTEMS This invention relates to pool cover systems, primarily for swimming pools.

According to the invention, a pool cover system comprises a pool cover with a cable extending across the leading edge of the cover and united therewith, means for causing the cover to move, in reversible directions, between pool covering and uncovering positions, and means for varying tension in said cable so as to cause said leading edge of the cover to be lifted or lowered.

The pool cover may comprise flexible sheet material. The means for causing such a cover to move between pool covering and uncovering positions may comprise, in the case of pool covering, cable and cable winding means. For pool uncovering, pool cover wind-up means may be provided.

Pool cover movement is preferably guided by guide members slidably located by a pair of laterally spaced channels extending in the direction of pool cover movement.

An embodiment of the invention will now be described, by way of example only, with reference to the accompanying semi-diagrammatic drawings, wherein: Figure 1 is a plan view of a pool cover system, Figures 2 to 10 are details thereof, to enlarged scales, and Figures 11 and 12 illustrate details of a modification.

With reference to Figures 1 and 2, a water-filled swimming pool 10 is provided with a pool cover system 1 comprising a pool cover 2 of flexible sheet material, and a cable 3 extending across the leading edge 4 of the cover 2 and united therewith. The cover 2 and cable 3 are united by folding back a short length of the leading edge 4 over a flexible tube of, for example, PVC extending substantially parallel to the leading edge, and then securing the short length in place so as to trap the tube, and form a tunnel 5; threading the cable 3 through the tunnel/tube so formed. The cover 2 is of rectangular plan form.

The pool cover system 1 further comprises separate means for causing the cover 2 to move, in reversible directions, between pool covering and uncovering positions, and means 20 for varying tension in the cable 3 so as to cause the leading edge 4 of the cover 2 to be lifted or lowered, relative to water in the pool.

The separate means for causing the cover 2 to move between pool covering and uncovering positions comprise a cable 6 and cable winding means 7 therefor, for pool covering, and pool cover wind-up means 8, for pool uncovering. Pool covering and uncovering movement is indicated by arrows 9, 11 respectively.

The cable winding means 7 comprise a windlass driven by a gearbox unit 52 by way of a clutch 55. The cable 6 extends forwardly from the drum of the windlass 7, in the general direction of arrow 9, then around a guide pulley 12, to reverse in direction before connection to the cover 2 by way of a right hand front shackle 60, which also connects cable tensioning means 20 (described below) to the cover 2.

Pool cover movement is guided by guide members (not shown) slidably located by a pair of laterally-spaced, substantially parallel, channel-type tracks, also not shown, but represented by arrows 15, 16, extending in the direction of pool cover movement 9. Our UK Patent No. 2199741, to which reference is directed, discloses details of a suitable pool cover guide arrangement employing channel-type tracks.

As best shown in Figure 2, the means 20 for varying tension in the leading edge cable 3 comprise a cable tensioning pulley 21, a slotted link 22, a drive cable anchor 23, and a crank 24 (see also Figures 3 and 4). One end, (the left-hand end) of the leading edge cable 3 is anchored, in an adjustable manner, so as to vary tension in the cable, to a front shackle 25 on the opposite or left-hand side of the cover 2. The other, or right-hand end of the cable 3 is anchored to the tensioning pulley 21, by way of a clamp screw 14, or any other suitable fixing. The anchor 25 may comprise an adjustable length screw shackle.

The means 20 is movable as the cover 2 moves, being guided by the track represented by arrow 16.

One end of the link 22, which link serves as a connecting rod, is slidably attached to a peripheral part of the pulley 21 by a pin 31. The other end of the link 22 is pivotally attached to one end of a rod 27 slidably located by a guide block 28. A stop 29 is adjustably mounted on the rod 27. The guide block 28 moves with the means 20 and is mounted on the front right-hand shackle 60. The drive cable anchor 23 is secured to the end of the rod 27 remote from the link 22.

As best shown in Figures 3 and 4, the link 22 is formed with a longitudinally extending slot 30 which receives the pin 31 carried by the pulley 21, whereby the link 22 is pivotally as well as slidably attached to the pulley. The slot 30 allows some relative movement between the pulley 21 and the link 22.

As explained hereinafter, the slot 30 also allows the tension pulley 21 to be rotated by the lever 22, so as to apply tension to the leading edge cable 3 when the pool cover 2 is "parked", as shown in Figure 4.

The crank 24 extends laterally from the shaft 32 of the pulley 21 and is connected to a roller 33 movable on a track 34 which incorporates a cam surface 35. The track 34 is preferably the pool cover guide track on that side of the pool 10, ie the track represented by the arrow 16 in Figure 1.

The pin 31 is preferably mounted in an eccentric manner on the pulley 21, so as to allow fine adjustment of the pin relative to the pulley.

With reference once more to Figure 1, a secondary cable 40 extends forwardly from the left-hand front shackle 25 around a guide pulley 41, rearwardly to around a pulley 42, across the pool 10 to a pulley 43, then forwardly again, through shackle 60 of means 20, where it is slidably attached, through right-hand cable anchor 23 (or, alternatively, secured to another part of the means 20). The arrangement causes tension to be applied to the cable 6.

As mentioned above, the cable 6 extends forwardly from the right-hand anchor point 23 around the guide pulley 12, and then rearwardly to the windlass 7. The gearbox unit 52, which drives the windlass 7, also rotates the pool cover wind-up means 8, which comprises a roller 53, rotatable between the gear-box unit 52 and an end bearing 51.

In operation, the pool cover 2, which is initially rolled up on the roller 53, is pulled over the pool 10, in the direction of arrow 9, by winding up the cable 6, using the windlass 7. The roller 53 is decoupled from the windlass 7 to allow this.

Tension in the cable 6, applied by the windlass 7, is transmitted to the cable anchor 23, so as to move it in the direction of the cover movement.

This movement of the anchor 23 carries the rod 27 forwardly with it until the stop 29 on the rod is brought into contact with the guide 28. The forward movement of the rod 27 causes the link 22 to rotate the tension pulley 21 in the direction of arrow 62. Rotation of the pulley 21 applies tension to cable 3, lifting the leading edge of the cover 2 clear of water in the pool 10. Thus the leading edge 4 is substantially prevented from "scooping" pool water as the pool cover 2 is moved to a pool covering position. Figures 3 and 7 refer. When such lifting has been achieved, further tension in cable 6, still applied by the windlass 7, results in forward movement of the cover 2. As shown in Figure 1, the means 20 is mounted on the right-hand front shackle 60. However, the means 20 and shackle 60 can be mounted on either the left or right-hand side of the cover 2. When on the right-hand side (as in Figures 1, 9 and 10), a secondary cable, namely cable 40, is attached to the shackle 60 so as to transmit tension around pulleys 43, 42, 41 to left-hand front shackle 25. When the means 20 is mounted on the left-hand side of the cover 2, (as in Figures 11 and 12), a continuous single cable, (namely cable 70). is used, which runs from the windlass 7, round pulley 12 and through hole 73 in an anchor 72, where a slug 71 is crimped on it so that tension produced by the windlass 7 pulls the slug against the anchor 72, thus transmitting tension to the right-hand side of the cover 2. The cable 70 continues round pulleys 43, 42, 41 and is then attached to cable anchor 23 and means 20, which is now disposed at the left-hand front shackle 60. (This assembly is a mirror image of the right-hand front arrangement described above.). Note in both systems, one front shackle has the means 20 thereon, whereas the other shackle is passive. This arrangement pulls the right-hand side of the cover 2 against a stop (not shown), allowing the cable 70 freedom in one direction only, namely during uncovering.

As shown in Figure 4, in the pool covering parked position of the cover 2, the roller 33 is engaged with the cam surface 35 whereby still further tension is applied to the cable 3, so that the leading edge 4 of the cover 2 is secured. Note at this point the front edge of the cover 2 extends about 400 mm on to the pool surround. The added tension produced by the cam surface 35 tightens the front edge of the cover 2 so that it cannot be lifted by a child. See also Figure 8 which illustrates the pool cover in the fully "parked" position.

With reference to Figures 5 and 6, to uncover the pool 10, tension in the cable 6 is released by operation of the clutch incorporated in the windlass 7. As the clutch disengages from the windlass 7, it simultaneously engages with the roller 53, so as to allow withdrawal, ie rearward movement, of the cover 2 by rotation of the roller 53. Release of tension in the cable 6 also results in relaxation of tension in the leading edge cable 3, and rotation of the tension pulley 21 to be reversed in the direction of the arrow 65. Pool uncover movement also results in withdrawal of the roller 33 from the cam surface 35, as well as withdrawal of the stop 29 from the guide 28.

The result is release of tension in the leading edge cable 3, whereby the leading edge 4 of the pool cover 2 is lowered (under the influence of gravity) towards the water in the pool 10. Any rainwater which may have collected on the pool cover, can now discharge itself into the pool.

With further reference to Figure 12, the arrangement whereby the cable 70 can slide through hole 73 of cable anchor 72, until the crimped slug 71 contacts the anchor so as to apply tension to the cable 70, is advantageous.

The advantage provided by this modification is apparent on uncovering the pool 10, as both the left-hand and right-hand sides of the cover 2 are free to wind around the drum 53 at slightly different rates. This differences improves smoothness of cover winding and reduces the power required for the winding.

The invention avoids the need for a beam or similar rigid structure mounted on the leading edge of a pool cover.

Claims

CLAIMS 1. A pool cover system comprising a pool cover with a cable extending across the leading edge of the cover and united therewith, means for causing the cover to move, in reversible directions, between pool covering and uncovering positions, and means for varying tension in said cable so as to cause said leading edge of the cover to be lifted or lowered.
2. A pool cover system as claimed in claim 1, wherein the pool cover comprises flexible sheet material.
3. A pool cover system as claimed in claim 1, wherein the means for causing the cover to move between pool covering and uncovering positions comprise, in the case of pool covering, cable and cable winding means.
4. A pool cover system as claimed in claim 2 or 3, wherein the means for causing the cover to move between pool covering and uncovering positions comprise, in the case of pool uncovering, pool cover wind-up means.
5. A pool cover system as claimed in any one of claims 1 to 4, wherein pool cover movement is guided by guide members slidably located by a pair of laterally spaced channels extending in the direction of pool cover movement.
6. A pool cover system as claimed in any one of claims 1 to 5, wherein the pool cover and the cable extending across the leading edge of the cover are united by folding back the leading edge over a flexible tube extending substantially parallel to the leading edge and then securing the folded back portion of the leading edge so as to trap the tube and form a tunnel for receiving the cable.
7. A pool cover system as claimed in any one of claims 3 to 6, wherein the pool cover cable wind-up means comprise a windlass driven by a gearbox unit by way of a clutch.
8. A pool cover system as claimed in claim 7, wherein the windlass is disposed at the wind-up end of the pool cover and the wind-up cable extends forwardly from the windlass, then around a guide pulley, to reverse in direction before connection to a fixing device at an adjacent end of the pool cover leading edge.
9. A pool cover system as claimed in claim 8, wherein the fixing device also connects the cable tensioning means to the pool cover.
10. A pool cover system as claimed in claim 8 or 9, wherein the fixing device comprises a shackle.
11. A pool cover system as claimed in any one of claims 8, 9 or 10, wherein a further cable extends rearwardly from said fixing device, around a first guide pulley at one side of the pool, across the pool cover, around a second guide pulley at the opposite side of the pool, and then forwardly to a fixing device at the leading edge of the pool cover, said fixing devices being disposed at opposite ends of the leading edge.
12. A pool cover system as claimed in any one of claims 1 to 11, wherein the means for varying tension in the cable extending across the leading edge of the pool cover comprises a pulley operable by rotation to tension said cable and drive means for rotating said pulley.
13. A pool cover system as claimed in claim 12, wherein the drive means is operable by pool cover movement.
14. A pool cover system as claimed in claim 13, wherein the pulley drive means comprise a link pivotally mounted on one end of the pulley and operable by pool cover movement by way of cam means.
15. A pool cover system as claimed in claim 14 wherein the cam means comprise a cam roller mounted on the non-pivotal end of the lever and a stationary cam surface disposed adjacent one side of the pool.
16. A pool cover system as claimed in claim 15, when dependant from claim 5, wherein the cam surface is provided by one of the laterally-spaced channels of claim 5.
17. The combination of a pool cover systems as claimed in any one of claims 1 to 16, and the pool it is intended to cover.
18. A pool cover system substantially as hereinbefore described, with reference to the accompanying drawings.
19. The combination of claim 17, substantially as hereinbefore described, with reference to the accompanying drawings.