Abstract: Driving device for a watercraft, which device comprises a water flow channel (10) which is connected to the watercraft, preferably to the bottom thereof, and which has an inlet (11) and an outlet (12), a drive shaft (13, 14) which extends into said channel (10), a bearing shaft (15) coaxially arranged with the drive shaft part (14) in said channel, a first rotating impeller (21) connected to the drive shaft (13) for rotation in said channel (10) for the movement of water in either direction between the inlet (11) and the outlet (12), a second impeller (22) which is contra-rotating to the first impeller (21) and connected to the bearing shaft (15) for rotation in said channel (10) for the movement of water in said direction between the inlet (11) and the outlet (12), and that the drive shaft (13, 14) and the bearing shaft (15) are connected to each other via a planetary-like gearing (30), wherein one of said impellers (21, 22) is formed with an impeller casing (31) which is provided with an outer surface (322)

Abstract: Driving device for a watercraft, which device comprises a water flow channel (10) which is connected to the watercraft, preferably to the bottom thereof, and which has an inlet (11) and an outlet (12), a drive shaft (13, 14) which extends into said channel (10), a bearing shaft (15) coaxially arranged with the drive shaft part (14) in said channel, a first rotating impeller (21) connected to the drive shaft (13) for rotation in said channel (10) for the movement of water in either direction between the inlet (11) and the outlet (12), a second impeller (22) which is contra-rotating to the first impeller (21) and connected to the bearing shaft (15) for rotation in said channel (10) for the movement of water in said direction between the inlet (11) and the outlet (12), and that the drive shaft (13, 14) and the bearing shaft (15) are connected to each other via a planetary-like gearing (30), wherein one of said impellers (21, 22) is formed with an impeller casing (31) which is provided with an outer surface (322)

Abstract: Hub assembly for the journalling of an impeller (4) or drive shaft end (3) in the pump housing (2) of a water jet propulsion unit for propulsion of a vessel. The hub assembly forms a separate, integrated assembly (6) which as a single unit can be assembled and dismounted from the stem without requiring the pump housing, impeller or drive shaft to be removed from the vessel. The hub assembly is joined together by means of a tightening nut (15), screwed onto a sleeve (9), with an inwardly positioned bearing plate (16) axially holding the sleeve in a bearing housing (8) while concurrently clamping the bearings (10, 11) between said bearing plate and a radially extended flange (17), arranged in the front end of the sleeve, so that the bearing housing, the bearings and the sleeve form a separate, integrated unit.

Abstract: The present invention relates briefly to a jet propulsion assembly for ships, the assembly including a propeller pump of an axial or a semiaxial type. The propeller pump has a pump housing (6), the inlet of which is connected to a water inlet channel and the outlet of which is connected to an outlet device. In the water flow channel through the pump housing a pump wheel (11) is rotably journalled in a stationary casing (8). A drive shaft (12) of the pump wheel (11) extends from a drive unit through the water inlet channel to the pump wheel (11). The pump wheel (11) and the drive shaft (12) are connected by a flexible coupling (13) which is essentially torsional resistant but permits angular deviations between the drive shaft (12) and the rotational shaft of the pump wheel (11).

Abstract: A reversing device of a jet propulsion assembly for ships. The jet propulsion assembly includes a steering means connected to the outlet of a pump, for steering the driving water jet, the steering means including two flaps for reversing the driving water jet. An actuator pivots a first flap downwards around a first bearing across the water jet, at the same time as link arms, which are journalled between the front edges of the first flap and second flap, swing the second flap around a second bearing. The rear portion of the second flap is thereby raised towards the water jet and encounters the inner side of the first flap in such a way that both flaps shut off the passage rearwards and divert the water jet obliquely downwards/forwards.