BACKGROUND ART Swimming pool cleaners generally operate by being attached to the pump line of a swimming pool, typically in the weir. Water is drawn through the cleaner and through the hose. The cleaner will typically include a valve which open and closes continuously and sequentially, causing the cleaner to be moved by the force produced by rapidly closing and opening this valve.

A well-documented problem with automatic swimming pool cleaners is that they tend to become locked in a particular cleaning pattern which does not necessarily result in it traversing the entire bottom of the pool. This leaves unsightly dirty patches.

In addition, the cleaner has a tendency to become stuck in certain areas, particularly around the pool steps. Often this requires manual intervention, without which the cleaner will remain stuck for long periods, often to detriment of gears and other working parts of the cleaner.

This problem may be exacerbated by the fact that the swimming pool hose lies mainly on the surface of the water and can become partially set in a particular bent or twisted configuration which also contributes to the movement thereof in a fixed pattern.

It is therefore an object of this invention to provide a device or an arrangement which assists in enabling the cleaner to extricate itself from tight locations n the pool and also to move in random patterns over the bottom and sides of the pool.

DISCLOSURE OF THE INVENTION According to the invention, a device for promoting free movement of a hose of an automatic swimming pool cleaner, includes means for attachment to the hose of the pool cleaner and means for rotating the hose about its longitudinal axis.

In operation, the continuous but gradual or incremental rotation of the pool hose to which the cleaner is attached, ensures that firstly, the cleaner cannot become set in a regularly repeated pattern of movement and secondly, should it become stuck in a particular location, the twisting thereof enables the hose to gradually change the orientation of the pool cleaner until it is no longer obstructed, thereby allowing it to move off in a different direction.

In a preferred form of the invention there is provided a device for promoting free movement of a hose of an automatic swimming pool cleaner, including a coupling between adjacent portions of hose or between the hose and the cleaner or the pump; the coupling including two elements each being locatable in or over or at the ends of the hose portions, and means associated with the coupling to cause at least one element to rotate so that its portion of hose rotates longitudinally.

The device of the invention is preferably locatable in line with the hose and in the proximity of the weir of the pool.

In the preferred form of the invention in which only one of the coupling elements is rotatable, the device comprises a housing including an inlet and an outlet for the flow of water, the inlet being attachable to a first length of hose to which is attached the pool cleaner, and the outlet being attachable to a second length of hose linked to the swimming pool pump ; the housing including a connector securable to the first length of hose at one end and rotatably mounted on the inlet of the housing at the other, the housing including means for rotating the connector to effect rotation of the hose about its longitudinal axis.

In the preferred form, the rotating means is adapted to rotate the hose gradually or incrementally. In this form, the rotation is effected by a pin indexer.

The housing is provided with a passage linking the inlet and outlet, and including a rotary element rotatable by the flow of water through the housing.

In the preferred form of the invention, the rotor comprises a paddle wheel orientated to rotate in the plane of the flowing water, the paddle wheel being mounted on a shaft including a gear and the gear engaging a series of decreasing gears which in turn engage a pin indexer, the indexer in turn effecting rotation of an outer gear associated with a rotatable connector element affixed to the hose. In this form, the rotatable connector is rotatably mounted on the inlet connector of the device.

In an alternative form of the invention in which both coupling elements are mutually, longitudinally rotatable, the rotor comprises an impeller rotatable in a plane perpendicular to the direction of flow of the water. Rotation of the impeller effects rotation of an outer gear which engages a plurality of gears spaced apart circumferentially and fixed to a gear holder, the gear holder in turn comprising the tubular connector element for engaging the hose, such that rotation of the impeller effects rotation of the gear holder and hence the hose.

In this form of the invention, the impeller effects rotation of both lengths of pipe i. e. either side of the device of the invention.

In either or both of the above forms of the invention, rotation of the hose is preferably effected at a rate of six degrees per minute.

Faster or slower rotation may be achieved by setting the indexer, and/or changing the sizes of the gears.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is an isometric front view of a device according to the invention; Figure 2 is an isometric bottom view of the device; Figure 3 is an exploded isometric view of the device; Figure 4 is a sectional view along line A-A; Figure 5 is a sectional view along line B-B; Figure 6 is a sectional view along line C-C; Figure 7 is a sectional view along line D-D; Figure 8 is a sectional view along line E-E; Figure 9 is a front isometric view of an alternative form of the device; Figure 10 is a rear isometric view of the device; Figure 11 is an exploded isometric view of the device; and Figure 12 is a sectional view along line A-A of Figure 9.

DESCRIPTION OF THE BEST MODE In Figures 1 to 8, a device 10 for promoting free movement of the hose of a swimming pool cleaner thereby ensuring that it does not become stuck, comprises a housing 12 having an inlet 14 and an outlet 16 for water which is pumped through passage 18 in the housing under the influence of a swimming pool circulation pump.

The inlet and outlet are tubular connectors which in the drawings, firmly engage the inner diameter of the swimming pool hose. The inlet connector 14 is rotatably mounted on inlet tube 20.

Located within the passage 18 is a paddle wheel 22 which is rotatable on transverse shaft 24. The water flow through the passage engages the vanes 26 of the paddle wheel 22 causing it to rotate. The transverse shaft includes a gear 28 which engages the inner

gear 30 of a series of four decreasing gears 32 which transmit the rotation to pin indexer 34 which is engaged by outer drive gear 36.

The crank 38 of the indexer 34 causes the ratchet arm 40 to engage ratchet gear 42 mounted on one end of the shaft 44.

When the ratchet gear 42 is rotated by the indexer, outer gear 36 rotates the inlet connector 14, thereby causing rotation of the hose to which it is coupled.

Typically, the indexer is set to rotate the housing six degrees every minute, in the direction of arrow 46. Spacer 48 is located between the end of the transverse shaft and the gearbox cover 49.

In an alternative form of the invention 50 as shown in Figures 9 through 12, the rotary element is an impeller 52 rotatable transversely to the direction of flow of the water (as indicated by arrow 54). In this form of the invention, the impeller 52, is rotated by the water flow and in turn transmits the motion to each of three circumferential gears 60. The circumferential gears 60 are mounted on a gear holder 62 having three mounting pins 64 on which the gears 60 are statically mounted. Rotation of the three gears 60 occurs simultaneously to generate torque enabling the gear holder to be rotated, thereby rotating the hose to which it is connected.

As the inlet side 66 of the housing is statically connected to the hose into which it has been inserted, rotation of the house attached thereto rotates simultaneously and at the same rate as the hose attached to the gear holder 62.