Abstract: A prefabricated building panel comprises a wooden grid of crossing longitudinal and transverse studs which are notched to interengage at the crossing points, one array of studs having surfaces coinciding with one major surface of the panel and having opposed surfaces recessed from the opposite major surface of the panel and vice-versa. The studs which are made of standard dimension lumber provide adequate nailing surfaces on each of the major surfaces of the panel for attachment of finish sheeting such as drywall thereto after installation. The panel may include molded in situ insulation and provides on the inner side of the panel large longitudinally recessed channels through which electric wiring, plumbing and the like can be ducted.

Abstract: A suction head for a swimming pool cleaner comprising a housing which is open at its lower side and has inclined bristles attached to its lower edge for supporting on a surface to be cleaned. The housing has a rotary sleeve mounted to its top for connection of a suction hose in turn to be connected to a water suction pump. Said sleeve opens in a chamber within the housing in which a vibratory element is pivotally mounted, said element having a crescent or air-foil shape. By a flow of water sucked through said chamber, the vibratory element is automatically brought into a vibrating movement which imparts pulsations on the suction head. Thereby, the inclined bristles are bent and straightened repetitively, resulting in a forward thrust moving the suction head over the surface to be cleaned. At least one foot is disposed in the housing which is cyclically displaced vertically by a driving mechanism driven by the movement of the vibratory element and returned by return springs.