Abstract: An apparatus and method for cleaning the bottom and vertical side walls of a swimming pool, pond or tank employs a robotic, self-propelled cleaner having a protective housing of conventional design, the cleaner being operated at a primary cleaning speed as it traverses the surfaces to be cleaned and until the cleaner housing emerges from the water along a sidewall of the pool; thereafter the cleaner operates at a secondary drive speed that is relatively slower than the primary speed and the cleaner thereafter reverses direction and descends for a pre-determined period of time at the slower secondary speed in order to permit the air entrained under the housing to escape without destabilizing the cleaner during descent. After the predetermined period of time, the cleaner resumes operation at the more rapid primary speed until the cleaner housing once again emerges from the water's surface, after which the cycle is repeated.

Abstract: A self-contained, manually propelled pool cleaner moves on wheels positioned inboard of the housing, the wheels being supported by axles that extend laterally across the entire width of the housing and are secured at their ends to the side walls and along their length to the lower periphery of the front and rear walls to provide structural integrity and rigidity to the housing. The base plate is provided with pivoting brushes extending diagonally across the direction of travel to move debris towards the intake ports for entrainment in a disposable filter bag. A pivoting off-set connector permits the operator to control the direction of movement by axially twisting the handle while pushing or pulling the cleaner. Electrical power to operate the water pump(s) is supplied from an airtight floating battery case that is tethered to the pool cleaner.

Abstract: Directional control means are provided for robotic swimming pool or water tank cleaner of the type having an internal filter bag for removing and retaining debris from the pool, an electric pump for drawing water through the filter bag and two parallel motor driven cylindrical brushes for propelling the cleaner along and sweeping the bottom surface of the pool, said control means including one or more water activated hydraulic cylinders located on the side of the cleaner between the brushes, each containing a leg adapted to project downwardly to contact the pool bottom and partially lift one side of the cleaner. As the cleaner moves along the pool bottom it pivots around the projected leg to change direction. Manual or automatic means can be provided to activate the hydraulic legs.

Abstract: A dispenser for smoothly and reliably dispensing flowable or particulate matter such as fish food is provided, in which dynamic gravity of the matter itself is utilized to regulate dispensing of the same in an uncomplicated manner. The dispenser has a container adapted to be mounted upon a rotatable shaft and having a hollow interior with two openings therethrough for communicating with external surroundings. A partition is mounted within the container interior for dividing a portion of the container interior into a plurality of compartments. The partition extends between the openings to limit quantity of matter falling into one of the compartments as the container rotates. A duct is mounted to rotate with the container and communicates with one of these openings. As the container rotates, the partition regulates the quantity of matter falling into the dispensing compartment and directs matter not discharged from the dispensing compartment back into the other compartment.