Abstract: A method for detecting foreign particles in a liquid, the method may include transmitting transmitted pulses of radiation, by a transmitter, towards a liquid conduit that is filled with liquid; wherein the transmitted pulses comprises pulses that differ from each by being associated with absorbance frequencies of different foreign particles; receiving, by a receiver, received pulses that propagated through liquid as a result of the transmission of the multiple transmitted pulses; comparing between the transmitted pulses and the received pulses to provide a comparison result; determining a liquid contamination based on the comparison result; and cleaning, by a cleaning unit, the liquid conduit with a cleaning solution; wherein a cleaning material of the cleaning solution is supplied from a compressible cleaning material reservoir.

Abstract: A method for detecting foreign particles in a liquid, the method may include transmitting transmitted pulses of radiation, by a transmitter, towards a liquid conduit that is filled with liquid; wherein the transmitted pulses comprises pulses that differ from each by being associated with absorbance frequencies of different foreign particles; receiving, by a receiver, received pulses that propagated through liquid as a result of the transmission of the multiple transmitted pulses; comparing between the transmitted pulses and the received pulses to provide a comparison result; determining a liquid contamination based on the comparison result; and cleaning, by a cleaning unit, the liquid conduit with a cleaning solution; wherein a cleaning material of the cleaning solution is supplied from a compressible cleaning material reservoir.

Abstract: A self-propelled cleaning apparatus for cleaning a submerged surface of a pool including a housing having an interior chamber, a plurality of supports rotationally mounted to a lower portion of the housing arranged to move the cleaning apparatus over the surface of the pool. At least one inlet and at least one outlet, and a filter and a water pump disposed in the interior chamber, the water pump configured to establish a flow path through the housing by drawing water and debris from the pool into the housing through the at least one inlet, directing water through the filter, and discharging filtered water out of the housing to the pool through the at least one outlet, wherein the at least one outlet is configured to direct a pressurized stream of water at an acute angle with respect to the surface over which the apparatus moves.

Abstract: A robotic pool or tank cleaner is propelled by water jets, the direction of which is controlled by the direction of rotation of a reversible pump motor that is horizontally mounted in the pool cleaner housing that has a propeller attached to either end of the motor drive shaft which projects from opposing ends of the motor body, each of the propellers being positioned in, or near a water jet discharge conduit that terminates in discharge ports at opposite ends of the housing. Each discharge conduit has a pressure-sensitive flap valve downstream of the respective propellers. When the propellers rotate in one direction, the water is drawn through one or more openings in the base plate, passes through one or more filter assemblies associated with the pool cleaner and is discharged through one of the discharge ports as a water jet of sufficient force to propel the pool cleaner.

Abstract: A robotic pool or tank cleaner is propelled by water jets, the direction of which is controlled by the direction of rotation of a horizontally mounted pump motor within the pool cleaner housing, having a propeller attached to either end of the motor drive shaft which projects from opposing ends of the motor body, each of the propellers being positioned in a water jet discharge conduit that terminates in discharge ports in opposing ends of the housing. Each discharge conduit has a pressure-sensitive flap valve downstream of the respective propellers. When the propellers rotate in one direction, the water is drawn through one or more openings in the base plate, passes through one or more filter assemblies associated with the pool cleaner and is discharged through one of the discharge ports as a water jet of sufficient force to propel the pool cleaner along the surface being cleaned.

Abstract: A self-propelled cleaning apparatus for cleaning a submerged surface of a pool or tank includes a housing having a front portion as defined by the direction of movement of the apparatus when propelled by a water jet, an opposing rear portion and adjoining side portions defining the periphery of the apparatus, and a baseplate with at least one water inlet. Rotationally-mounted supports are coupled proximate the front and rear portions of the housing to enable movement of the apparatus over the submerged surface. A water pump is configured to draw water and debris from the pool through the inlet for filtering. A stationary directional discharge conduit is in fluid communication with the pump and has at least one discharge opening through which a pressurized stream of water forming the water jet is directionally discharged at an acute angle with respect to the surface over which the apparatus is moving.

Abstract: A self-propelled cleaning apparatus for cleaning a submerged surface of a pool or tank includes a housing having a front portion as defined by the direction of movement of the apparatus when propelled by a water jet, an opposing rear portion and adjoining side portions defining the periphery of the apparatus, and a baseplate with at least one water inlet. Rotationally-mounted supports are coupled proximate the front and rear portions of the housing to enable movement of the apparatus over the submerged surface. A water pump is configured to draw water and debris from the pool through the inlet for filtering. A stationary directional discharge conduit is in fluid communication with the pump and has at least one discharge opening through which a pressurized stream of water forming the water jet is directionally discharged at an acute angle with respect to the surface over which the apparatus is moving.

Abstract: A self-propelled cleaning apparatus for cleaning a submerged surface of a pool or tank includes a housing having a front portion as defined by the direction of movement of the apparatus when propelled by a water jet, an opposing rear portion and adjoining side portions defining the periphery of the apparatus, and a baseplate with at least one water inlet. Rotationally-mounted supports are coupled proximate the front and rear portions of the housing to enable movement of the apparatus over the submerged surface. A water pump is configured to draw water and debris from the pool through the inlet for filtering. A stationary directional discharge conduit is in fluid communication with the pump and has at least one discharge opening through which a pressurized stream of water forming the water jet is directionally discharged at an acute angle with respect to the surface over which the apparatus is moving.

Abstract: The base plate of a robotic or manually propelled tank or pool cleaning apparatus includes a transverse conduit positioned on the interior surface of the base plate and is in fluid communication with a source of pressurized water that is also located within the pool cleaner's housing, which pressurized water is discharged from the bottom or lower portion of the transverse conduit through a plurality of openings that extend along a line that is transverse to the longitudinal axis of the pool cleaner's direction of travel, to produce downwardly-directed water jets that are discharged through and below the base plate towards the surface of the pool or tank over which the pool cleaning apparatus is moving to dislodge and suspend dirt and debris that is then drawn into and retained by the pool cleaner's filter.

Abstract: A robotic pool or tank cleaner is propelled by water jets, the direction of which is controlled by the direction of rotation of a horizontally mounted pump motor within the pool cleaner housing, having a propeller attached to either end of the motor drive shaft which projects from opposing ends of the motor body, each of the propellers being positioned in a water jet discharge conduit that terminates in discharge ports in opposing ends of the housing. Each discharge conduit has a pressure-sensitive flap valve downstream of the respective propellers. When the propellers rotate in one direction, the water is drawn through one or more openings in the base plate, passes through one or more filter assemblies associated with the pool cleaner and is discharged through one of the discharge ports as a water jet of sufficient force to propel the pool cleaner along the surface being cleaned.

Abstract: A self-propelled robotic pool cleaner (100) has a first pair of driven brushes (12, 14) and second pair of free brushes co-axially mounted for rotation on axles (16) at the opposite ends of the pool cleaner. The first pair of brushes are mounted on one side and are driven by a drive motor (110); the second pair of brushes are mounted on the opposite side of the cleaner. A rotational delay clutch (30) is co-axially positioned between each pair of the first and second brushes so that reversing the drive motor causes the first pair of driven brushes to temporarily rotate at an angular rotational velocity that is greater than that of the second pair of brushes, thereby pivoting the pool cleaner through a predetermined angular change in direction before the synchronous rotation of the second pair of dual brushes is initiated by the engagement of the clutch.

Abstract: A self-propelled cleaning apparatus for cleaning a submerged surface of a pool or tank includes a housing having a front portion as defined by the direction of movement of the apparatus when propelled by a water jet, an opposing rear portion and adjoining side portions defining the periphery of the apparatus, and a baseplate with at least one water inlet. Rotationally-mounted supports are coupled proximate the front and rear portions of the housing to enable movement of the apparatus over the submerged surface. A water pump is configured to draw water and debris from the pool through the inlet for filtering. A stationary directional discharge conduit is in fluid communication with the pump and has at least one discharge opening through which a pressurized stream of water forming the water jet is directionally discharged at an acute angle with respect to the surface over which the apparatus is moving.

Abstract: A self-propelled cleaning apparatus for cleaning a submerged surface of a pool or tank includes a housing having a front portion as defined by the direction of movement of the apparatus when propelled by a water jet, an opposing rear portion and adjoining side portions defining the periphery of the apparatus, and a baseplate with at least one water inlet. Rotationally-mounted supports are coupled proximate the front and rear portions of the housing to enable movement of the apparatus over the submerged surface. A water pump is configured to draw water and debris from the pool through the inlet for filtering. A stationary directional discharge conduit is in fluid communication with the pump and has at least one discharge opening through which a pressurized stream of water forming the water jet is directionally discharged at an acute angle with respect to the surface over which the apparatus is moving.

Abstract: A robotic pool or tank cleaner is propelled by water jets, the direction of which is controlled by the direction of rotation of a horizontally mounted pump motor within the pool cleaner housing, having a propeller attached to either end of the motor drive shaft which projects from opposing ends of the motor body, each of the propellers being positioned in a water jet discharge conduit that terminates in discharge ports in opposing ends of the housing. Each discharge conduit has a pressure-sensitive flap valve downstream of the respective propellers. When the propellers rotate in one direction, the water is drawn through one or more openings in the base plate, passes through one or more filter assemblies associated with the pool cleaner and is discharged through one of the discharge ports as a water jet of sufficient force to propel the pool cleaner along the surface being cleaned.

Abstract: A self-propelled robotic pool cleaner (100) has a first pair of driven brushes (12, 14) and second pair of free brushes co-axially mounted for rotation on axles (16) at the opposite ends of the pool cleaner. The first pair of brushes are mounted on one side and are driven by a drive motor (110); the second pair of brushes are mounted on the opposite side of the cleaner. A rotational delay clutch (30) is co-axially positioned between each pair of the first and second brushes so that reversing the drive motor causes the first pair of driven brushes to temporarily rotate at an angular rotational velocity that is greater than that of the second pair of brushes, thereby pivoting the pool cleaner through a predetermined angular change in direction before the synchronous rotation of the second pair of dual brushes is initiated by the engagement of the clutch.

Abstract: A pool cleaner includes a housing having a front, rear and adjoining side portions and a base plate having a water inlet. A pump is configured to draw water and debris from the pool through the inlet for filtering and discharge filtered water through an outlet. A pair of wheels are coupled proximate the front and rear of the housing, each of which is coupled to an opposing end of an axle, each opposing end of the axle being slidably moveable along the housing in a forward and rearward directional path of the cleaner in response to a steering assembly. An on-board controller includes memory for storing a cleaning program, and a processor electrically coupled to the memory to execute the cleaning program to automatically control the steering assembly to position each end of the axles to steer the cleaner while it is moving in a forward or reverse direction.

Abstract: A method and apparatus for controlling the directional movement of a self-propelled robotic pool cleaner having at least one pair of rotational support members for propelling and cleaning a surface of a pool. The method includes accelerating the at least one pair of rotational support members of the pool cleaner from a stopped position to a first predetermined rotational rate in a first predetermined time period; rotating the at least one pair of rotational support members at said first predetermined rotational rate for a second predetermined time period; and increasing the first rate of rotation to a second greater predetermined rotational rate, wherein said pool cleaner is propelled at a normalized rate for cleaning said pool.

Abstract: A base plate for a self-propelled robotic cleaning apparatus for cleaning a submerged surface of a pool or tank. The base plate includes a bottom surface and a water inlet formed therethrough, and an inlet extension member configured to mount in the water inlet. The inlet extension member is slidably retractable and extendable in a direction that is normal relative to the bottom surface of the base plate. A height adjustment mechanism is coupled to the inlet extension member and configured to move the inlet extension member upwardly and downwardly in the normal direction relative to the bottom surface of the base plate. The height adjustment mechanism can be adjusted manually. Alternatively, at least one sensor is operably coupled to a controller to automatically control the height adjustment mechanism.

Abstract: A robotic pool or tank cleaner is propelled by water jets, the direction of which is controlled by the direction of rotation of a reversible pump motor that is horizontally mounted in the pool cleaner housing that has a propeller attached to either end of the motor drive shaft which projects from opposing ends of the motor body, each of the propellers being positioned in, or near a water jet discharge conduit that terminates in discharge ports at opposite ends of the housing. Each discharge conduit has a pressure-sensitive flap valve downstream of the respective propellers. When the propellers rotate in one direction, the water is drawn through one or more openings in the base plate, passes through one or more filter assemblies associated with the pool cleaner and is discharged through one of the discharge ports as a water jet of sufficient force to propel the pool cleaner.

Abstract: A baseplate for a robotic self-propelled pool cleaner having one or more inlet openings through which water-borne debris passes prior to filtration is provided with downwardly depending inlet extension members having walls that define an opening corresponding in shape to the baseplate inlet opening and that are mounted in close-fitting relation to extend the water intake opening towards, but without touching, the pool surface to increase the suction force at the surface. The baseplate optionally includes a rotatable wheel mounted in an inboard recess in the baseplate on, or adjacent to the longitudinal centerline of the cleaner to facilitate passage over obstacles that would immobilize the pool cleaner by contact with an inlet extension member.