Abstract: This invention relates to a relief valve used where there is an induced flow through equipment. The relief valve controls the flow through the equipment at a uniform rate and also provides for pressure relief of the liquid used in the equipment. The valve comprising a body having a flow passage therethrough with an inlet and an outlet for connection into a pipe having induced flow therethrough. A bypass passage from the body between the inlet and the outlet and open to ambient conditions at the free end is also provided. There is a flexible resilient diaphragm in the bypass passage perforated to permit flow therethrough in one direction only and the perforation variable in size dependant on the degree of flexing of the diaphragm.

Abstract: A swimming pool cleaner comprising a forwardly inclined body having a flow passage therethrough, an inlet foot having a water inlet foot being attached to the body and connected to the flow passage and when in use, is proximate to a surface to be cleaned, a flexible disc surrounding the water inlet and rotatably connected to the inlet foot and having a peripheral edge, and a stop for preventing upward flexing of the peripheral edge beyond a predetermined amount located forward of the body and substantially above and inward of the peripheral edge.

Abstract: This invention concerns automatic swimming pool cleaner accessories which may be used to prevent such pool cleaners from following a substantial fixed pattern over a submerged surface to be cleaned and consists of a collar shaped to firmly engage the flexible hose used with a pool clenar, the collar having a plurality of projections extending radially from the collar. The projections may be stems terminating in spherical members at their outer ends.

Abstract: This invention is concerned with flexible plastics material discs which are shaped to engage around the inlets to automatically operating swimming pool cleaners which are caused to move by an interruption of the flow induced through the cleaner by the pump of the pool filtration plant. The discs act to hold the cleaner against the surface to be cleaned and the invention provides guides on the upper surface of the disc preferably in the form of radially extending ribs decreasing in height towards the periphery of the disc. The guides direct dirt over the disc into the inlet of the pool cleaner.