Abstract: A suction pool cleaner for cleaning of a pool surface, the pool cleaner comprising a housing having a debris inlet for suction-drawn flow of water and debris, a first leg assembly and a second leg assembly, each leg assembly being pivotable with respect to the housing, each leg assembly having a rotatable loop track for moving the pool cleaner over the pool surface, the tracks being selectively rotatable in a first direction and an opposite second direction, wherein when the tracks are rotated in opposite directions to one another, the leg assemblies pivot with respect to the housing in opposite directions, thereby lifting the debris inlet away from the pool surface such that suction force between the debris inlet and the pool surface is reduced along with the footprint provided by each track such that less power is required to turn the pool cleaner.

Abstract: A pool cleaner water surface diverter 7 that will break the pool water surface 1 before the pool cleaner 4 reaches the surface, or at least before the suction of the cleaner 4 is able to suck in air. A rim 12 extends beyond a physical envelope of the cleaner, such as being wider than is the cleaner. Ideally the diverter has neutral or near neutral buoyancy in the pool water. A central hub on a pool hose 5 allows rotation of the diverter relative to the hose. compartments/containers may contain a substantially buoyancy neutral fluid or material in water e.g. PVA foam.

Abstract: The specification discloses apparatus (10) for excavating a trench (18) and preparing a base region of the trench (18) for laying of a pipeline, cabling or the like therein, the apparatus (10) including a trench forming machine (11) driven in a forward direction (14) while excavating the trench (18), the appraatus (10) also including a device (13) for laying bedding material in the base region of the trench, the device (13) being integrally part of the trench forming machine (11) or being towed thereby, the apparatus (10) further including conveyor means (20, 22, 23) for conveying excavated trench material created by the trench forming machine (11) to the device (13) for laying bedding material into the trench (18), the device (13) including a vibrating screen separator (25) for separating fine particulate material from coarser excavated trench material whereby the fine particulate material is delivered to the base region of the trench (18).

Abstract: A pool cleaner, including a valve chamber (4) having an inlet and two outlet orifices and a valve (7) within the valve chamber. The valve continuously oscillates between first and second positions due to water flow through the chamber from the inlet to the outlet orifices. A bias means (8), in the form of resilient projections on the valve (17), the valve being offset in the chamber or a stiff projection from the valve (13) contacting the wall of the valve chamber. The bias means applies an eccentric influence on the valve such that the operator does not need to initiate oscillation of the valve.