Abstract: Treatment devices for fluid such as water are described. Principally (although not necessarily exclusively) designed for use as chlorinators, the devices may divert water flowing in conduits into the devices for treatment and subsequent return to the flow stream. A return tube of the device may be designed to create vortex action, using a pressure differential to evacuate treated water from the device back into the conduit.

Abstract: Devices for cleaning vessels, especially swimming pools, are discussed. The devices may include repositionable in-line valves, with the valves typically moving laterally (from side to side) and changing the initial direction of the main fluid-flow path through the valves and corresponding cleaner bodies. Asymmetric feet may be utilized as part of the devices, whose bottom bearing surfaces may include elongated strips of material placed parallel to the normally-forward direction of travel of the devices. Discs of non-uniform flexibility also may be employed, and blocking tabs or gripping material may be used to inhibit undesired backward movement of a cleaner when its operation commences.

Abstract: Separate covers for protruding portions of discs of automatic swimming pool cleaners are addressed. The covers may be placed onto protrusions, such as fins, and removed from the fins as needed. Version of the covers are made of material more rigid and having lower coefficient of friction than the fins to discourage lateral bending of the fins and decrease frictional contact of the fins with pool surfaces.

Abstract: Devices for cleaning vessels, especially swimming pools, are discussed. The devices may include repositionable in-line valves, with the valves typically moving laterally (from side to side) and changing the initial direction of the main fluid-flow path through the valves and corresponding cleaner bodies. Asymmetric feet may be utilized as part of the devices, whose bottom bearing surfaces may include elongated strips of material placed parallel to the normally-forward direction of travel of the devices. Discs of non-uniform flexibility also may be employed, and blocking tabs or gripping material may be used to inhibit undesired backward movement of a cleaner when its operation commences.

Abstract: The invention relates to a method for controlling an automatic device for cleaning a surface immersed in liquid which comprises electric motors for driving a chassis along a cleanable surface. The inventive method consists in periodically measuring at least one electrical quantity which makes it possible to obtain the representative value of the resisting torque of at least one driving electric motor (7), in comparing each obtained value with the predetermined threshold representative value of a maximum acceptable value and, when said value is greater than said threshold value for the driving electric motor (7), a procedure known as a protection procedure is started.

Abstract: Devices for cleaning vessels, especially swimming pools, are discussed. The devices may include a non-linear flow path in a gap surrounding an in-line valve. This non-linearity permits lengths of concentric pipes forming the gap to be decreased without sacrificing operational performance of the devices. Valves forming parts of the cleaning devices may be diaphragms but shaped, sized, reinforced, or configured differently than existing valves and may have collapsible segments whose interior shape resembles an ellipse in transverse cross-section. Co-molding of diaphragms and pipes may occur, and inner and outer cups may be used to fix relative positions of various components of the devices.