Marine craft jet drive - has pump with two rotors rotating in opposite directions

摘要

The water jet propulsion for marine craft has a pump with an inlet at the forward facing end and an outlet in the form of a nozzle at the stern end. The pump has at least two stages and the impeller (4) of the final stage rotates in the opposite direction to the impeller (11) of the preceding stage, either at the same speed or at a different speed. The drive (8,9,12) to the two impellers is enclosed within the impeller hubs (3,10). The drive is transmitted through a shaft (7) with a bevel pinion (8) which engages two bevel gears (9,12) mounted on opposite sides of the drive shaft (7) and attached to the hubs of the impellers. USE - Marine craft propulusion.