Abstract: A hydraulic power generating apparatus which can be easily disposed in a water channel, such as a waterway or a water conducting pipe. The hydraulic power generating apparatus comprises a horizontal rotor supporting housing (4) having a rotor, a holding body (5) erected on an upper surface of the rotor supporting housing (4), a support ring (2) in which the rotor supporting housing (4) is fixed, and a power generator (11). The rotor supporting housing (4) is integrally fixed within the support ring (2) by the holding body (5). The power generator (11) is disposed on the upper part of the holding body (5) protruding from the support ring (2), and the support ring (2) is formed with attachment portions (2A, 2B) for fixing the rotor supporting housing (4) in a water channel.

Abstract: A positive-pressure floating type airplane comprising an airfoil portion, left-right fuselages, a central fuselage, an elevator and a rudder disposed at the back of the airfoil portion, a thruster disposed at the back of the central fuselage, and a horizontal stabilizer disposed at the rear ends of the left-right fuselages. The individual front ends of the airfoil portion, the left-right fuselages and the central fuselage are formed into arcuate shapes in longitudinal sections. On the lower side of the airfoil portion, a recessed air capture is formed from the front end to the rear end. As a result, the positive-pressure floating type airplane is floated by the reaction from the air at the time when the air to pass the air capture through the airfoil portion is pushed by the thrust of the thruster, and is propelled forward by the component of that thrust.

Abstract: Provided is a quiet propeller including a propeller blade having such a pitch angle not at its root portion but at its blade end edge portion with respect to a relative flow in the rotational direction, as to raise the internal pressure of a liquid thereby to eliminate a cavity, a water bubble or a cavitation at the blade root portion at the time of a high-speed rotation so that the propeller is rotated at a high speed by a small prime mover and by a prime mover capable of moving much fluid backward. In the quiet propeller, a propeller blade is curved backward at its leading end portion to form a slope portion, and a rotational front side end portion in the slope portion is formed into an arcuate shape in the side view whereas a rotational rear side end portion is so gradually extended backward from the rotational front side end portion as to become straight from the blade root to the blade end, thereby to form a deflecting slope face.

Abstract: A propeller, wherein the tip parts of the propeller blades of a horizontal-shaft windmill are tilted in the front direction of the propeller blades to form inclination parts. The inclination angle of the tilted parts is set within the range of 25 to 50° relative to the longitudinal direction of the propeller blades.