Propeller arrangement in a cathodic protection system

Patent metadata

Field	Value
Publication number	US-2022380907-A1
Application number	US-201917754982-A
Country	US
Kind code	A1
Filing date	Oct 18, 2019
Priority date	Oct 18, 2019
Publication date	Dec 1, 2022
Grant date	—

Abstract

The invention relates to a propeller arrangement in a cathodic protection system for a marine vessel with a marine propulsion system, which cathodic protection system comprises a direct current power source with a positive terminal. The propulsion system comprises at least one driveline housing at least partially submerged in water; a torque transmitting drive shaft extending out of the driveline housing; and at least one propeller mounted on the drive shaft. According to the invention, the at least one propeller is electrically isolated from its drive shaft. Each electrically isolated propeller is electrically connected to a slip ring connector, which slip ring connector is in electrical connection with the positive terminal. The invention further relates to a vessel provided with such a propeller arrangement.

First claim

1 . Propeller arrangement in a cathodic protection system for a marine vessel with a marine propulsion system, which cathodic protection system comprises a direct current power source; the propulsion system comprising;
at least one driveline housing at least partially submerged in water; a torque transmitting drive shaft extending out of the driveline housing; at least one propeller mounted on the drive shaft;
characterized in that
the at least one propeller is electrically isolated from its drive shaft;
each electrically isolated propeller is electrically connected to a slip ring connector;

which slip ring connector is in electrical connection with a terminal of the direct current power source.

2 . Propeller arrangement according to claim 1 , characterized in that each propeller hub has a slip ring connector attached to the hub upstream in the power flow direction.

3 . Propeller arrangement according to claim 1 , characterized in that the slip ring connector is annular and arranged surrounding and spaced from the drive shaft.

4 . Propeller arrangement according to claim 1 , characterized in that the slip ring connector is mounted onto an internal surface at one end of the propeller hub.

5 . Propeller arrangement according to claim 1 , characterized in that the slip ring connector is mounted between a first propeller hub and the driveline housing.

6 . Propeller arrangement according to claim 5 , characterized in that a further slip ring connector is mounted between a first propeller hub and a second propeller hub.

7 . Propeller arrangement according to claim 1 , characterized in that each slip ring connector is made from an inert metallic material.

8 . Propeller arrangement according to claim 1 , characterized in that the at least one propeller is made from an inert metallic material.

9 . Propeller arrangement according to claim 1 , characterized in that a torque transmitting electrically isolating component is mounted between the at least one propeller and the drive shaft.

10 . Propeller arrangement according to claim 1 , characterized in that a dielectric shield is provided between the at least one propeller and the drive shaft.

11 . Propeller arrangement according to claim 10 , characterized in that the dielectric shield comprises a layer of dielectric material extending along the drive shaft over at least the entire axial extension of the propeller hub.

12 . Propeller arrangement according to claim 1 , characterized in that slip ring connector is in electrical connection with a positive terminal of the direct current power source, so that the at least one propeller forms an anode.

13 . Propeller arrangement according to claim 1 , characterized in that slip ring connector is in electrical connection with a negative terminal of the direct current power source so that the at least one propeller forms a cathode.

14 . Marine vessel characterized in that the marine vessel is protected by a propeller arrangement according to claim 1 .

Assignees

• Volvo Penta Corp

Inventors

• Raftegard Viktor
• Kallvik Johan

Classifications

• C23F13/20 Primary

  Conducting electric current to electrodes · CPC title

• B63B59/04

  Preventing hull fouling (anti-fouling paints C09D5/16) · CPC title

• C23F2213/31

  Immersed structures, e.g. submarine structures · CPC title

• B63H1/20

  Hubs; Blade connections · CPC title

• B63B39/061

  by using trimflaps, i.e. flaps mounted on the rear of a boat, e.g. speed boat · CPC title