| 摘要 |
PURPOSE:To reduce resistance for torque and effectively convert the torque to the propulsive force by jetting air bubble from the surface of the blades of a screw, and dissolving vortex generated on the surface of the blades at rotation of the screw. CONSTITUTION:A screw shaft 3 is formed with an air tube 3a as an air passage in the center, and the end part of the tube is connected to an air collecting device on the ship. Branch tubes 3b are branched from the air tube 3a and communicated into blades 6. When a hull is advanced, air is sucked from the air collecting device, and sent to the branch pipe 3b through the air tube 3a. At this time, because water is discharged through many air holes 6f... by centrifugal force, air is filled in the air tube 3a, branched tube 3b, and air passage 6h by the pressure from the air collecting device and the centrifugal force, and air is discharged from the air holes 6f as air bubble. Resistance of water at rotation of a screw 2 is reduced by air bubble. Further, water sucked in a water flow control cylinder 7 together with jetted air from the air holes 6f are pushed out into a nozzle part 7a so as to give propulsive force. |
