CN118103291A

CN118103291A - Propelling device

Info

Publication number: CN118103291A
Application number: CN202180103247.4A
Authority: CN
Inventors: L·朱利安; T·格罗; H·拜尔德; J·乔德
Original assignee: GE Energy Power Conversion Technology Ltd
Current assignee: GE Energy Power Conversion Technology Ltd
Priority date: 2021-10-15
Filing date: 2021-10-15
Publication date: 2024-05-28
Also published as: KR20240090396A; EP4416049A1; WO2023061605A1

Abstract

A propeller (1) for a vessel is described. The propeller comprises a plurality of blades (4) extending from a rotating housing (2). The blades (4 a) are distributed around the blade pitch diameter (D1) of the rotating housing. The mounting plate (14) rotatably mounts the rotary housing (2) to the hull (H) of the ship. The slewing bearing (16) includes a driven ring having a driven gear, which is fixed to the rotary housing (2), and a stationary ring, which is fixed to the mounting plate (14). The diameter (D2) of the slewing bearing (16) is at least 0.4 times the pitch diameter (D1) of the blade. The propeller (1) includes a main motor (28 a), the main motor (28 a) having a drive shaft (26 a) mechanically connected to a drive gear (24 a). The driven gear and the drive gear (24 a) of the slew bearing (16) define a single stage transfer gear with a transfer ratio between 5:1 and 15:1.

Description

Propelling device

Technical Field

The present invention relates to a propeller, and in particular to a propeller mountable to a hull of a ship for propulsion.

Background

Known propellers comprise a plurality of blades extending from a rotating housing, wherein each blade is pivotable about a respective blade axis by a blade actuator to provide thrust in any direction orthogonal to the rotational axis of the rotating housing. Such propellers are sometimes also referred to as cycloidal propellers, cycloidal propellers or propulsion units, and Voith-Schneider propellers operating in cycloidal or trochoid mode.

Each blade actuator may use one or more of a mechanical actuator, a hydraulic actuator, a pneumatic actuator, and an electric actuator (e.g., an electric motor) to pivot the respective blade about its blade axis.

Disclosure of Invention

The present invention provides a propeller for a ship which seeks to overcome some of the problems and disadvantages found in existing propellers. In particular, the invention provides a propeller for a vessel, the propeller comprising:

A rotary housing;

A plurality of blades extending from the rotating housing, each blade having a respective blade axis about which the each blade is pivotable relative to the rotating housing, and wherein the blades are distributed about a blade pitch diameter of the rotating housing;

A swivel bearing (or "swivel ring") comprising a slave ring fixed to the rotating housing and comprising a slave gear, and a stationary ring adapted to be fixed to the hull of the vessel, optionally by means of a mounting plate or mounting structure, wherein the diameter of the swivel bearing is at least 0.4 times the pitch diameter of the blades;

A main motor having a drive shaft; and

A drive gear (or "pinion") mechanically coupled to the drive shaft, wherein the driven gear and the drive gear define a single stage transfer gear, wherein the transfer ratio is between about 5:1 and about 15:1.

The term "mechanically coupled" as used herein includes both direct and indirect coupling between corresponding components, unless otherwise indicated.

The slew bearing may have any suitable configuration.

A plurality of rolling elements are typically positioned between the slave and stationary rings.

The slew bearing may comprise one or more annular grooves for receiving one or more static or dynamic seals for preventing water from entering the interior of the rotating housing. The rotating housing is typically surrounded by an annular collar forming a structural part of the hull of the vessel. Preferably, the inner surface of the collar has a profile that substantially conforms to the outer profile of the rotating housing, and an annular gap or clearance is provided between the rotating housing and the collar to allow the rotating housing to rotate freely. One end of the annular gap is open and the other end of the annular gap is closed, typically near a swivel bearing that interfaces the rotating part of the propeller with the stationary part of the propeller or the hull of the vessel. Preferably, a watertight seal is provided at the closed end of the gap to prevent any water in the gap from entering the rotating housing. The watertight seal may be provided by one or more static or dynamic seals received in one or more annular grooves of the slew bearing and/or by one or more seals provided on the collar.

The driven ring of the slew bearing may be secured to the rotating housing by a plurality of first mechanical fasteners distributed about a diameter of at least one driven link circle. Any suitable first mechanical fastener may be used, such as a bolt or screw received in aligned openings spaced around the circumference of the slave ring and rotating housing. Other means of securely fixing the driven ring to the rotating housing may be used. The driven ring may have a radial inner diameter, a radial outer diameter, and at least one driven link circle diameter. The driven gear may be formed as an integral part of the driven ring, or as a separate member that is fixed to the driven ring such that the driven ring and driven gear rotate together as an integral driven member of the slew bearing. If the driven gear is formed as an integral part of the driven ring, the teeth of the driven gear are formed on a surface of the driven ring, for example, on a radially inner surface, a radially outer surface, or an annular surface of the driven ring. If the driven gear is formed as a separate member, the driven gear may be formed as a ring and the teeth of the driven gear are formed on a surface of the ring, for example, on a radially inner surface, a radially outer surface, or an annular surface of the ring. The driven gear may be secured to the driven ring by a plurality of first mechanical fasteners (e.g., bolts or screws) that are also received in aligned openings spaced around the circumference of the driven gear. Other means of fixedly securing the driven gear to the driven ring may be used. The driven gear may have a radial inner diameter, a radial outer diameter, and at least one driven gear pitch diameter if formed as a separate member.

The stationary ring may be fixed to the hull of the vessel directly, or indirectly by means of a mounting plate or other intermediate mounting structure. In other words, the propeller may further comprise a mounting plate for rotatably mounting the rotary housing, and the mounting plate is fixed to the hull, for example to an annular collar surrounding the rotary housing. Such a mounting plate or mounting structure would be a stationary part of the propeller. The stationary ring may be secured by a second mechanical fastener. In one arrangement, the stationary ring may be secured to the mounting plate or to another stationary portion of the propeller by a plurality of second mechanical fasteners distributed around the diameter of at least one stationary ring segment circle. Any suitable second mechanical fastener may be used, such as a bolt or screw received in aligned openings spaced around the circumference of the stationary ring and mounting plate. Other means of securing the stationary ring to the hull or mounting plate of the vessel may be used. The stationary ring may have a radial inner diameter, a radial outer diameter, and at least one stationary ring segment circle diameter.

If the propeller includes a mounting plate or other intermediate mounting structure, the mounting plate or structure may be secured to the hull of the vessel in any suitable manner, including by a plurality of mechanical fasteners, such as bolts or screws. In one arrangement, the mounting plate may be secured to an annular collar that surrounds the rotating housing and forms a structural part of the hull of the watercraft. The mounting plate forms a stationary part of the propeller and may be used to mount components that do not need to rotate with the rotating housing, such as, for example, a main motor and any associated equipment.

The slave ring may be mounted at a flange of the rotary housing. The flange may be formed in a portion of the swivel housing facing the hull of the vessel or the mounting plate (if used). The slew bearing may define an opening (e.g., an access opening) that provides access from inside the hull of the vessel to the interior of the rotating housing.

The diameter of the slew bearing may be any suitable diameter for the driven ring, stationary ring, and driven gear (including those diameters mentioned above). The slew bearing may be configured as a rotating bearing having a radially inner ring and a radially outer ring, in which case the diameter of the slew bearing is preferably the diameter of the radially inner ring, e.g. the radially innermost diameter of the radially inner ring. But as explained above, the diameter may be any suitable diameter of the slew bearing such that in some propellers the radially inner portion of the slew bearing may have a diameter less than 0.4 times the pitch diameter of the blade, provided that the radially outer portion of the slew bearing has a diameter greater than or equal to 0.4 times the pitch diameter of the blade. The radially inner ring may be a slave ring and the radially outer ring may be a stationary ring, or vice versa. In a preferred arrangement, the driven ring is a radially inner ring, the stationary ring is a radially outer ring, and the driven gear is formed as a separate member (e.g., as a separate ring that is fixed to the driven ring). In this preferred arrangement, the teeth of the driven gear are arranged on the radially inner surface of the separate ring fixed to the driven ring, and the drive gear is positioned radially inward of the driven gear such that the teeth of the drive gear mesh with the teeth of the driven gear.

The diameter of the slew bearing is at least 0.4 times the blade pitch diameter (i.e., the diameter of the rotating housing passing through the blade axis). The diameter of the slew bearing may be less than 1.0 times the pitch diameter of the vane. In most practical arrangements, the diameter of the slew bearing will typically be less than 0.8 times the pitch diameter of the vane. It will thus be appreciated that the slew bearing has a relatively large diameter compared to corresponding slew bearings on known propellers. For example, depending on the overall size and design of the propeller, the blade pitch circle diameter may be between about 3m and about 11m, and the diameter of the slew bearing may be between about 1.2m and about 11m (or more preferably no greater than about 8.8 m). A tradeoff is made between the size of the slew bearing and the structural integrity and rigidity of the hull interface.

In the example of the first propeller, the blade pitch circle diameter may be between about 9m and about 11m, and the diameter of the slew bearing may be between about 3.6m and about 11m (or more preferably no greater than about 8.8 m). In the example of the second propeller, the blade pitch circle diameter may be between about 3m and about 5m, and the diameter of the slew bearing may be between about 1.2m and about 5m (or more preferably no greater than about 4 m). It will be readily appreciated that other examples are possible.

For example, the drive shaft of the main motor may be mechanically connected directly to the drive gear or indirectly by means of a main drive train.

In order to constrain the physical size and weight of the main motor, it is beneficial to use a slew bearing where the single stage transmission has the proper gear ratio. The physical size and weight of the main motor may then be comparable to the motors used in conventional marine propulsion. As mentioned above, the driven gear and the drive gear (or pinion) together define a single stage transfer gear, wherein the gear ratio is between about 5:1 and about 15:1. The gear ratio may be greater than about 5:1 (e.g., 6:1, 7:1,..14:1) or less than about 15:1 (e.g., 14:1, 13:1,..6:1). The gear ratio may be about 10:1. If the transmission ratio is about 10:1, it means that for each rotation of the driven ring of the slew bearing relative to the stationary ring, the drive gear will rotate about ten times. The driven gear and the driving gear may be suitably configured depending on the physical dimensions of the propeller, i.e. the number of teeth on the driven gear and the number of teeth on the driving gear may be selected to achieve a desired gear ratio. For a first propeller having a blade pitch diameter of between about 9m and about 11m, the rotating housing may be driven to rotate at a rotational speed of between about 10rpm and about 40rpm, depending on the mode of operation. More specifically, the rotary housing may be driven to rotate at a rotational speed of about 15rpm when operating in trochoid mode and about 30rpm when operating in trochoid mode. The drive shaft and drive gear of the main motor may rotate at a rotational speed between about 50rpm (10×5=50) and about 600rpm (40×15=600), depending on the gear ratio at full speed of the vessel. For a second propeller having a blade pitch diameter of between about 3m and about 5m, the rotating housing may be driven to rotate at a rotational speed of between about 20rpm and about 130rpm, depending on the mode of operation. Depending on the gear ratio, the drive shaft and drive gear of the main motor may rotate at a rotational speed between about 100rpm (20×5=100) and about 2000rpm (130×15=1950).

The propeller may include a second main motor to provide redundancy. The second main motor may comprise a second drive shaft and a second drive gear mechanically connected to the second drive shaft, e.g. directly or indirectly by means of a second main drive train. The driven gear and the second drive gear may define a second single stage drive gear that operates in parallel with the single stage drive gear.

The propeller may include any suitable number of main motors for driving the driven ring of the slew bearing, each main motor having a respective drive shaft mechanically coupled to a respective drive gear. Each drive gear will define a single stage drive gear with the driven gear of the slew bearing. Each single stage drive gear will operate in parallel to rotate the driven ring of the slew bearing, and thus the rotating housing. It will be appreciated that there is typically a practical limit to the number of main motors. This is because each main motor will introduce additional drive trains, drive gears, etc., with a corresponding increased risk of mechanical failure. It also requires additional electrical components in the main power supply that supplies electrical power to the main motor. For example, for each main motor, the main power supply may include a power converter or Variable Speed Drive (VSD) that allows control of the rotational speed of the drive shaft of the main motor, and a circuit breaker for electrically isolating the main motor in the event of a fault. The power converter or VSD can be configured to provide load sharing between the primary motors (e.g., they can be controlled in accordance with a "leader-follower" control architecture or similar architecture). This is beneficial in terms of reducing both the size of the main motor and the load applied to the teeth of the respective drive gears, and allows a higher gear ratio to be used.

Two or three main motors may be typical depending on the overall size of the propeller and its operating requirements. Each main motor will typically have the same configuration and each single stage drive gear will typically have the same gear ratio. The main motors may be regularly or irregularly spaced around the circumference of the slew bearing.

Each main motor may include a rotor mechanically coupled to the drive shaft and a stator having stator windings. The rotor may comprise rotor windings or permanent magnets.

Each main motor may have any suitable configuration and may use any suitable type of cooling, which may be air-cooled or liquid-cooled, for example. For example, each main motor may be a synchronous or asynchronous motor, and rotor windings or permanent magnets may be used to define rotor poles. The preferred arrangement is a liquid cooled synchronous permanent magnet motor which may be provided within a compact outer housing or shell. Such motors may be physically compact, making them easier to install and maintain. It also helps reduce the profile size of the cooling system that can wrap around the active portion of each main motor and in turn reduces the footprint of the propeller within the hull of the watercraft. The whole propeller is physically compact, which is beneficial for both the installation of the propeller inside the hull of the vessel and its continued maintenance and if necessary its repair.

Each primary motor may be mounted on a mounting plate or mounting structure (if used). If each main motor and each drive gear are positioned on opposite sides of the mounting plate, each drive shaft or main drive train may extend through a respective opening in the mounting plate.

Each drive train may include a mechanism for selectively disengaging the respective drive shafts from the driven ring such that they are no longer rotatably connected together. In one arrangement, each driveline may include a clutch mechanism between the drive shaft and the drive gear. When the clutch mechanism is closed, rotation of the drive shaft is transferred through the drive train to the drive gear to rotate the driven gear and thus the driven ring of the slew bearing. However, when the clutch mechanism is open, the drive shaft is effectively disengaged from the drive gear and rotation of the drive shaft is not transferred to the drive gear through the drive train, or vice versa, even though the teeth of the drive gear remain engaged with the teeth of the driven gear. In another arrangement, a suitable mechanism or coupling may move the drive gear away from the driven gear so that their teeth are no longer engaged. Such a mechanism for selectively disengaging the respective drive shaft from the driven ring may be particularly useful if each of the main motors is a permanent magnet motor, i.e., a motor having a rotor with rotor poles defined by a plurality of permanent magnets rather than rotor windings. In the event of an internal failure in one of the main motors, if its drive shaft is effectively disengaged from the driven ring of the slew bearing, the driven ring may continue to be driven into rotation by the other main motor(s) without causing any further detrimental rotation of the drive shaft (and hence rotor) of the main motor with the internal failure.

The drive shaft of each main motor may be aligned substantially parallel to the rotational axis of the rotary housing. The propeller is typically mounted to the hull of the vessel with the rotation axis of the rotary housing aligned substantially vertically, but in some arrangements the rotation axis may also be angled with respect to vertical or even aligned substantially horizontally.

Each primary motor may receive electrical power from a primary power source. The main power supply may be electrically connected to, or part of, the power distribution system of the vessel.

The propeller may further comprise a plurality of blade actuators. Each blade actuator may be mechanically coupled to a respective one of the blades for pivoting the blade about the blade axis. Each blade actuator defines an angle of the respective blade relative to the rotary housing. The blades extend axially from the surface of the rotating housing (i.e., away from the surface facing the hull or mounting plate (if used) of the vessel). Thus, the blade axis is substantially parallel to the rotational axis of the rotary housing.

Each blade actuator may use one or more of a mechanical actuator, a hydraulic actuator, a pneumatic actuator, and an electric actuator to pivot the respective blade about its blade axis. In a preferred arrangement, each blade actuator may comprise one or more motors. Each blade actuator motor may have any suitable configuration. For example, each blade actuator motor may be a synchronous or asynchronous motor, and rotor windings or permanent magnets may be used to define rotor poles. The vane actuator motor may sometimes be operated in a regenerative mode during operation of the propeller. The electric power generated by the vane actuator motor during this regeneration mode may be supplied to the auxiliary motor by an auxiliary power source. ( Indeed, it will be appreciated that a relatively small fraction (e.g., 2-3%) of the mechanical energy provided by the rotation of the rotating housing may be recovered by the regeneration mode, wherein the vane actuator motor operates as a generator. At other times, the vane actuator motor operates as a motor to pivot the corresponding vane about the vane axis or maintain a desired vane angle as the rotary housing rotates. )

The auxiliary motor is configured to drive rotation of the rotary housing in parallel with the main motor. The auxiliary motor may have any suitable configuration and will typically be significantly smaller than the main motor. In one arrangement, the auxiliary motor may be mounted to a stationary portion of the propeller, such as a mounting plate or other mounting structure, or to the hull of the vessel, and may include an auxiliary drive train mechanically connected to the driven ring of the slew bearing. This allows the auxiliary motor to rotate the driven ring of the slew bearing. The driven ring of the slewing bearing can be driven directly by the auxiliary drive train, or by means of a driven gear or by means of a separate driven gear which is also fixed to the driven ring. For example, the auxiliary drive train may mechanically connect the drive shaft of the auxiliary motor to the driven ring of the slew bearing. The auxiliary drive train may include an auxiliary drive gear, or the auxiliary drive gear may be mechanically coupled directly to the drive shaft of the auxiliary motor. The driven gear (or a separate driven gear) and the auxiliary drive gear of the slew bearing may define a single stage drive gear. Alternatively, the auxiliary motor may drive the rotary housing using a direct drive or a multi-stage drive gear. The auxiliary drive gear may be positioned radially inward of the driven gear of the slew bearing such that the teeth of the auxiliary drive gear mesh with the teeth of the driven gear.

In another arrangement, the auxiliary motor may be mounted to the rotating housing and may include an auxiliary drive train mechanically connected to an auxiliary stationary gear, which may be mounted to a stationary portion of the propeller, such as a mounting plate or other mounting structure. This allows the auxiliary motor to rotate the rotary housing to which the auxiliary motor is fixed. The auxiliary drive train may mechanically connect the drive shaft of the auxiliary motor to the auxiliary stationary gear. The auxiliary drive train may include an auxiliary drive gear, or the auxiliary drive gear may be mechanically coupled directly to the drive shaft of the auxiliary motor. The auxiliary stationary gear and the auxiliary drive gear mounted to the stationary portion of the propeller may define a single stage transfer gear. The teeth may be provided on a radially outer surface of the auxiliary stationary gear, and the auxiliary drive gear may be positioned radially outward of the auxiliary stationary gear such that the teeth of the auxiliary drive gear mesh with the teeth of the auxiliary stationary gear. It will be readily appreciated that other arrangements are possible. The drive shaft of the auxiliary motor may be substantially parallel to the axis of rotation of the rotary housing.

Any electrical energy recovered by the vane actuator motor during the regeneration mode may be converted by the auxiliary motor into mechanical energy that may be used to help drive the rotating housing. In an alternative arrangement, any electrical power generated by the blade actuator motor may be fed back into the main power supply for supplying electrical power to the main motor(s).

In some cases, the auxiliary motor may operate as a generator to supply electrical energy to one or more blade actuator motors for initial energization of the blade actuator motors, such as at start-up. This avoids the need to provide such power from a battery or other power source.

The invention further provides a method of operating a propeller, wherein each blade actuator comprises an electric motor, and the propeller further comprises an auxiliary electric motor for driving the driven ring. The method comprises supplying electrical power recovered by at least one of the blade actuator motors during the regeneration mode to the auxiliary motor, i.e. wherein the at least one blade actuator motor operates as a generator to generate electrical power, which is then supplied to the auxiliary motor.

During normal operation, the propeller may generate thrust for propelling the vessel through the water. The propeller may also function as a passive rudder or an active rudder depending on the speed of the ship, i.e. at high speeds and at low speeds.

The propeller may also operate as a turbine. For example, if a vessel is propelled through the water by one or more additional propellers or other types of propulsion units, the action of the water on the propeller's multiple blades may cause the rotating housing to rotate. The rotation of the rotary housing will be transmitted to the drive shaft of the main motor by means of the driven gear and the drive gear of the slew bearing, in which case the driven gear and the drive gear will act as a drive gear and a driven gear, respectively. The blade pitch control law may be optimized for turbine operation and in practice the blade pitch control law will be different from the blade pitch control law applied to generate thrust or as an active rudder or a passive rudder. The main motor is operable as a generator. In other words, the main motor may generate electric power that is supplied back to the main power supply.

In general, the propeller may be controlled according to one or more blade pitch control laws depending on the operational requirements. The blade pitch control algorithm applied will determine how each blade is independently pivoted about its respective blade axis by a respective blade actuator as the rotating housing is rotated by the main motor or by the action of water on the plurality of blades.

As explained above, the plurality of blades typically extend from a surface of the rotating housing facing away from the hull or mounting plate (if used) of the vessel. To facilitate ease of installation and repair or maintenance, the propeller may include a first empty access volume that extends axially from a first access opening in the surface of the rotating housing to a second access opening adjacent the slew bearing (i.e., at the other end of the rotating housing). The first access opening in the surface of the rotating housing is typically covered by a first removable access panel with a watertight seal to prevent any ingress of water into the interior of the rotating housing. The first access volume and the first and second access openings are preferably sized and shaped to fully receive the main motor therethrough. With such an arrangement, the present invention further provides a method of repairing or servicing a propeller, wherein:

the main motor is separate from the propeller (e.g., separate from the mounting plate);

Removing the first access panel; and

The main motor is fully received through the second access opening, the first access volume, and the first access opening. This means that if the main motor needs to be removed for repair or repair, it can simply be separated and then lowered through the propeller without having to disassemble the propeller from the vessel. Suitable winch means may be provided for lifting and lowering the main motor.

The replacement main motor may also be mounted to the propeller in a similar manner. More specifically, the replacement main motor may be installed from below the hull of the vessel by lifting it through the propeller before attaching it to the propeller, for example to the mounting plate (if used).

For example, such installation, repair or maintenance may occur in a dry dock with respect to a ship.

If the propeller comprises a mounting plate or other mounting structure for rotatably mounting the rotary housing to the hull of the vessel, the propeller may further comprise a second empty entry volume extending axially from the second entry opening to a third entry opening in the mounting plate. The second access volume and the third access opening are preferably sized and shaped to fully receive the main motor therethrough. The third access opening may be covered by a second removable access panel. In such an arrangement, the propeller effectively comprises an empty access volume extending from the first access opening to the third access opening, both of which are preferably covered or closed by respective removable access panels. The second access opening is intermediate the first access opening and the third access opening and is simply an opening in the rotating housing (e.g., adjacent the slew bearing) that is not normally covered or closed by the access panel.

The propeller as described herein may be adapted to be mounted into the hull of a vessel from below. For example, if the propeller is to be mounted with the rotating housing inside an annular collar, the rotating housing may be mounted from below, as the slew bearing has a diameter smaller than the diameter of the surface from which the blades extend, the annular collar forming a structural part of the hull and defining an opening in the hull. If a mounting plate is used, it may pass through the hull opening in sections that can be assembled together. The assembled mounting plate may then be secured to the hull as described herein. A swivel housing with a fixed swivel bearing may be mounted from below the hull and provided up to the hull or mounting plate. The stationary ring is then secured to the hull or mounting plate. Alternatively, the swivel bearing may be fixed to the mounting plate separately, and then the rotary housing may be provided up to the swivel bearing and fixed to the slave ring.

The propeller may comprise one or more additional access openings covered by removable panels, which allow an engineer to access the interior of the rotating housing from inside the hull of the vessel. Access may be required for repair or repair and/or to allow removal or installation of any of the components located in the rotating housing. Additional access panel(s) may be provided in the mounting plate (if used).

The invention further provides a vessel comprising a propeller as described herein.

The invention further provides a propeller for a vessel, the propeller comprising:

A rotary housing;

A plurality of blades extending from the rotary housing, each blade having a respective blade axis about which the each blade is pivotable relative to the rotary housing by a respective blade actuator comprising a motor;

A slew bearing comprising a slave ring secured to the rotating housing and a stationary ring adapted to be secured to the hull of the vessel, for example, directly or indirectly using a mounting plate or some other mounting structure;

A main motor for driving the slave ring;

an auxiliary motor for driving rotation of the rotary housing;

a main power supply; and

An auxiliary power supply;

Wherein the main power source is electrically connected to the main power source and the auxiliary motor is electrically connected to at least one of the blade actuator motors through the auxiliary power source and is configured to receive electrical power recovered by the at least one blade actuator motor during a regeneration mode, i.e., when the at least one blade actuator motor is operated as a generator.

A rotary housing;

a plurality of blades extending from a surface of the rotating housing, each blade having a respective blade axis about which the each blade is pivotable relative to the rotating housing;

a slew bearing comprising a slave ring secured to the rotating housing and a stationary ring adapted to be secured to the hull of the vessel, for example, directly or indirectly using a mounting plate or some other mounting structure; and

A main motor for driving the slave ring;

wherein the propeller further comprises an empty access volume extending axially from a first access opening in the surface of the rotating housing covered by the first removable access panel to a second access opening adjacent the slew bearing; and

Wherein the access volume and the first and second access openings are sized and shaped to fully receive the main motor therethrough.

Further features of the propeller are as described herein.

Drawings

FIG. 1 is a perspective view of a propeller according to the present invention;

FIG. 2 is a perspective view of the propeller shown in FIG. 1 mounted in the hull of a marine vessel;

FIG. 3 is a cross-sectional view of the mounted impeller shown in FIG. 2;

FIG. 4 is a detailed cross-section of the mounted propeller shown in FIG. 2, showing portions of a slew bearing;

FIG. 5 is a top view of the slew bearing and drive gear of the propeller of FIG. 1;

FIG. 6 is a cross-sectional view of the slew bearing and drive gear along line A-A of FIG. 5;

FIG. 7 is a detailed cross-sectional view of the slew bearing and drive gear shown in FIG. 5;

FIG. 8 is a perspective view of the slew bearing and drive gear shown in FIG. 5;

FIG. 9 is a perspective view of the slew bearing and drive gear shown in FIG. 5 with the main and auxiliary motors;

FIG. 10 is a schematic view of a first power supply system for a propeller according to the present invention;

FIG. 11 is a schematic view of a second power supply system for a propeller according to the present invention;

FIG. 12 is a schematic view of a propeller according to the invention installed in a vessel;

Fig. 13 to 15 are schematic views showing how a main motor can be separated and removed through a rotary housing of a propeller according to the present invention; and

Fig. 16 is a schematic view showing how a propeller according to the invention can be installed from below a ship.

Detailed Description

Referring to fig. 1 to 4, a propeller 1 for a ship includes a rotary housing 2. Six blades 4a,4 b..4 f extend axially from the lower surface 2a of the rotary housing 2. Each blade 4a,4b, 4f has a respective blade axis 6, each blade 4a,4b, 4f being pivotable relative to the rotary housing 2 about the respective blade axis 6 by a blade actuator 8. The propeller 1 comprises six blade actuators 8. Each blade actuator 8 comprises an electric motor 10 and a drive train 12, the drive train 12 comprising a drive gear for pivoting the respective blade. As shown in fig. 1, each blade 4a,4b, 4f is mounted in a respective blade module housing 36a,36b extending radially outwardly from the main body.

The blades 4a,4b, 4f are distributed around the blade pitch diameter D1 of the rotary housing 2 (i.e. the diameter of the rotary housing through the blade axis 6).

The propeller 1 comprises a mounting plate 14 for mounting the propeller to the hull of a vessel. The swivel bearing 16 is used to mount the rotary housing 2 to the mounting plate 14 such that it is free to rotate.

Fig. 2 to 4 show a propeller 1 mounted within an annular collar H forming a structural part of the hull of a marine vessel. The annular collar includes an upper annular surface H1, a first inner cylindrical surface H2, an inner frustoconical surface H3, and a second inner cylindrical surface H4. The inner surface H2 is adjacent the slew bearing 16 and the inner surfaces H3 and H4 define the inner contour of the collar which generally conforms to the outer contour of the rotating housing 2. The inner surfaces H3 and H4 of the rotating housing 2 and collar are separated by a gap G which allows the rotating housing to rotate freely. The gap G has an open end at the lower surface 2a of the rotary housing 2 and a closed end adjacent to the slew bearing 16. One or more static or dynamic seals (not shown) may be provided at the closed end to provide a watertight seal and prevent water from entering the interior of the rotating housing 2 through the slew bearing 16.

The mounting plate 14 is secured to the collar H by means of an intermediate securing structure (not shown) positioned between the lower surface of the mounting plate and the upper annular surface H1 of the collar.

As shown in more detail in fig. 5-9, the slew bearing 16 comprises a driven ring 18 secured to the rotating housing 2, a stationary ring 20 secured to the mounting plate 14, and a driven gear 22 secured to the driven ring 18. In an alternative arrangement, the stationary ring 20 may be directly secured to the hull of the vessel, such as the inner surface H2 of the collar.

The driven ring 18 defines a seat for receiving and positioning the driven gear 22. The driven ring 18 includes a plurality of openings 18a distributed around the driven link circle diameter. The driven gear 22 is located in a seat defined by the annular surface 18b and the cylindrical surface 18c of the driven ring 18. The driven gear 22 includes a plurality of openings 22a distributed about the driven gear pitch diameter, the openings 22a being aligned with the openings 18a in the driven ring 18. The driven ring 18 and the driven gear 22 are fixed together and to the rotary housing 2 by a plurality of bolts (not shown) which are received in the alignment openings 18a and 22a, and in the corresponding alignment openings 2b in the rotary housing. A plurality of teeth 22b are formed on the radially inner surface of the driven gear 22.

The driven ring 18 and the driven gear 22 together define an integral driven member of the slew bearing 16 for rotating the rotary housing 2 relative to the mounting plate 14. In an alternative arrangement, the drive gear may be formed as an integral part of the drive ring.

The stationary ring 20 includes a plurality of openings 20a distributed around the diameter of the stationary ring segment circle. The stationary ring 20 is secured to the mounting plate 14 by a plurality of bolts (not shown) that are received in openings 20a and in corresponding aligned openings in the mounting plate.

The stationary ring 20 is located radially outward of the driven ring 18 and the driven gear 22.

A plurality of rolling elements (not shown) are positioned between the driven ring 18 and the stationary ring 20.

The diameter D2 of the slewing bearing is at least 0.4 times the pitch diameter D1 of the blade. The diameter D2 of the slewing bearing is preferably smaller than 0.8 times the pitch diameter of the blade. In this example, diameter D2 is the radial outer diameter of driven gear 22, i.e., the interface between the driven gear and driven ring 18. It will be readily appreciated that diameter D2 may also be:

The radial inner diameter of the slave ring,

The radial outer diameter of the slave ring,

-The diameter of the circle of the driven link,

The radial inner diameter of the driven gear,

The pitch diameter of the driven gear wheel,

The diameter of the rolling elements between the slave ring and the stationary ring,

The radial inner diameter of the stationary ring,

-Radial outer diameter of stationary ring, or

For example, stationary ring diameter.

In this example, the blade pitch diameter D1 is about 10m and the diameter D2 is about 6.7m, which is in the preferred range of about 4m to about 8 m.

Two drive gears 24a and 24b (or "pinions") are located radially inward of the driven gear 22. The first drive gear 24a is mechanically coupled to a drive shaft 26a of a first main motor 28 a. The second drive gear 24b is mechanically coupled to a drive shaft 26b of a second main motor 28 b.

The driven gear 22 and the first drive gear 24a define a first single stage transfer gear 30a. The driven gear 22 and the second drive gear 24b define a second single stage transfer gear 30b that is parallel to the first single stage transfer gear 30a.

In this example, the gear ratio of the first single stage drive gear and the second single stage drive gear is 10:1. Each of the first drive gear 24a and the second drive gear 24b has twelve teeth, and the driven gear 22 has one hundred twenty teeth around its radially inner surface. If the gear ratio is 10:1, it means that for each rotation of the driven ring 22 of the slew bearing relative to the stationary ring 20 fixed to the mounting plate 14, each drive gear 24a and 24b will rotate about ten times.

In this example, the rotary housing 2 may be driven to rotate at a rotational speed of about 15rpm when operating in trochoid mode and at a rotational speed of about 30rpm when operating in trochoid mode. The drive shafts 26a and 26b of the first and second main motors 28a and 28b and the first and second drive gears 24a and 24b may rotate at rotational speeds of about 150rpm and about 300rpm depending on the operating mode.

The first and second main motors 28a, 28b are liquid-cooled permanent magnet motors.

The first main motor 28a and the second main motor 28b are mounted on the mounting plate 14. More specifically, each of the first and second motors 28a, 28b has an outer housing or shell secured to the upper surface of the mounting plate 14. Because the first and second main motors 28a and 28b and the first and second drive gears 24a and 24b are positioned on opposite sides of the mounting plate, each drive shaft 26a and 26b extends through a respective opening in the mounting plate 14.

The drive shafts 26a and 26b of the first and second main motors 28a and 28b are aligned substantially parallel to the rotational axis of the rotary housing 2.

The first main motor 28a and the second main motor 28b receive electric power from a main power source. The main power supply may be electrically connected to, or part of, the power distribution system of the vessel. Fig. 10 shows a first power supply system 100 for a propeller. The rotating portion of the first power supply system is generally indicated by the dashed box 102 and the stationary portion is indicated by the dashed box 104. Four vane actuator motors 10a,10b, 10d are located in the rotary housing 2 and are thus shown in the rotary part. Each blade actuator motor 10a,10b, 10d is mechanically connected to a respective inverter 106a,106b, by means of a slip ring 108a,108 b. Inverters 106a,106b, 106d are electrically connected to rectifier 110 by DC link 112. The rectifier 110 is electrically connected to a power distribution system 114 of the vessel. The first main motor 28a is also electrically connected to the power distribution system 114 of the watercraft by way of a main power converter or Variable Speed Drive (VSD) 116. Although not shown, it will be readily appreciated that the second main motor 28b may be electrically connected to the power distribution system in a similar manner. The primary power converter or VSD116 is part of the primary power source.

The vane actuator motor 10 may sometimes experience a regenerative mode during operation of the propeller 1. The electric power generated by the vane actuator motor 10 during this regeneration mode may be supplied to the auxiliary motor 32 by an auxiliary power source. Fig. 11 shows a second power supply system 200 for a propeller 1. The rotating portion of the power supply system is generally indicated by dashed box 202 and the stationary portion is indicated by dashed box 204. Four vane actuator motors 10a,10b, 10d are shown in the rotating part. Each blade actuator motor 10a,10b, 10d is mechanically connected to a respective inverter 206a,206b, 206d. The inverters 206a,206b, 206d are electrically connected to the rectifier 208 by means of slip rings 210. The rectifier 208 is electrically connected to the power distribution system 212 of the vessel. The auxiliary motor 32 is in a stationary portion and is also electrically connected to the DC link 214 by way of an auxiliary power converter or VSD216 that forms part of an auxiliary power source. The first main motor 28a is electrically connected to the power distribution system 212 of the vessel by way of a main power converter or VSD 218. Although not shown, it will be readily appreciated that the second main motor 28b may be electrically connected to the power distribution system in a similar manner. The primary power converter or VSD218 is part of the primary power source.

As shown in fig. 9, the third (or auxiliary) drive gear 24c is located radially inward of the driven gear 22. The third drive gear 24c is mechanically connected to a drive shaft 34 of the auxiliary motor 32. The driven gear 22 and the third drive gear 24c define a third single stage transfer gear 30c. Although the auxiliary motor 32 is positioned below the third drive gear 24c in fig. 9, this is only to clearly show the third single stage transfer gear 30c. In practice, the auxiliary motor 32 is mounted on a stationary part of the propeller (such as the mounting plate 14) and will therefore be positioned above the third drive gear 24c in a similar manner to the main motor. In an alternative arrangement, not shown, the auxiliary motor is fixed to the rotary housing and the third drive gear meshes with an auxiliary stationary gear fixed to the stationary part of the propeller.

Any electrical energy recovered by the vane actuator motor 10 during the regenerative mode of operation may be converted into mechanical energy that may be used to help rotate the rotating housing, for example, to drive the driven ring 18 of the slew bearing 16. In particular, as shown in fig. 11, any electrical power generated by one or more of the blade actuator motors 10a,10b, 10d may be supplied to the DC link 214 and then to the auxiliary motor 32 by way of the auxiliary power converter or VSD 216. The electric power supplied to the auxiliary motor 32 is used to rotate the third drive gear 24c to drive the driven ring 18 of the slew bearing 16. In the above-mentioned alternative arrangement, the electric power supplied to the auxiliary motor is used to rotate a third drive gear that rotates the auxiliary motor fixed to the rotary housing relative to the auxiliary stationary gear.

In an alternative arrangement, any electrical power generated by the blade actuator motor 10 may be fed back into the main power supply for supplying electrical power to the first and second main motors 28a, 28 b.

The mounting plate 14 includes an upper main access panel 38 and two smaller access panels 40a and 40b. The upper main access panel 38 covers an upper access opening 42 in the mounting plate 14 that is sized and shaped to fully receive the main motors 28a and 28b. The smaller access panels 40a and 40b cover access openings that allow engineers to access the interior of the swivel housing 2 from the vessel interior and are located radially inward of the slew bearing 16.

The lower surface 2a of the swivel housing 2 comprises a lower main access panel 44. The lower main access panel 44 covers a lower access opening 46 in the rotary housing 2, which is also sized and shaped to fully receive the main motors 28a and 28b. A watertight seal is maintained between the lower main access panel 44 and the swivel housing 2 to prevent water from entering the interior of the swivel housing.

The central portion of the interior of the swivel housing 2 is devoid of any means or equipment to create an empty access volume 48, the empty access volume 48 extending axially between the upper and lower access openings 42, 46 covered by the upper and lower main access panels 38, 44. The empty access volume 48 further comprises an intermediate access opening 50, the intermediate access opening 50 being defined by the swivel bearing 16 and through the intermediate access opening 50 the interior of the swivel housing 2 is accessible from above. Thus, the empty access volume 48 may be considered to include a lower access volume 48a extending between the lower access opening 46 and the intermediate access opening 50 in the lower surface 2a of the swivel housing 2, and an upper access volume 48b extending between the intermediate access opening and the upper access opening 42 in the mounting plate 14.

Fig. 13-15 show how one of the main motors 28b can be removed through the propeller so that a replacement main motor can be installed in its place without the need to remove the entire propeller. In particular, fig. 13 shows the upper main access panel 38 removed, and the main motor 28b separated from the mounting plate 14 and any associated equipment (e.g., cooling system or auxiliary equipment). Fig. 14 shows the lower main access panel 44 removed from the lower surface 2a of the swivel housing. Fig. 15 shows how the separate main motor 28b can be lowered as indicated by the block arrows by winch cables passing through the upper and lower access openings 42, 46 in the mounting plate 14 and the lower surface 2a of the swivel housing. The main motor 28b will pass unobstructed adjacent the slew bearing 16 through the intermediate access opening 50 and through the empty access volume 48. The replacement main motor may be mounted through the propeller in a similar manner, i.e. lifted by winch cables through the lower surface 2a of the swivel housing 2 and the lower and upper access openings 46, 42 in the mounting plate 14, before being attached to the mounting plate. Fig. 16 shows how the propeller is adapted to be fitted into the collar H from below the vessel. In particular, fig. 16 shows an intermediate stage of installation in which the mounting plate 14 is at least partially disassembled, passed through the opening in the collar H, and reassembled and secured to the collar. The main motors 28a and 28b are also attached to the mounting plate 14. The rotary housing 2 and its internals and equipment can then be mounted into the collar from below as indicated by the block arrows. The driven ring 18 and the driven gear 22 of the slewing bearing 16 have been fixed to the rotary housing 2. Once the rotating housing 2 is mounted into the collar H, the stationary ring 20 is fixed to the mounting plate 14 (or directly to the hull) and the blades may be mounted to the blade module.

Claims

1. A propeller (1) for a vessel, the propeller comprising:

A rotary housing (2);

A plurality of blades (4 a,4b,) extending from the rotary housing (2), each blade (4 a,4b,) 4f having a respective blade axis (6), each blade (4 a,4b,) 4 f) being pivotable relative to the rotary housing (2) about the respective blade axis (6), and wherein the blades (4 a,4b,) 4 f) are distributed about a blade pitch diameter (D1) of the rotary housing (2);

-a swivel bearing (16) comprising a driven ring (18) fixed to the rotary housing (2) and comprising a driven gear (22), and a stationary ring (20) adapted to be fixed to the hull of the vessel, wherein the diameter (D2) of the swivel bearing (16) is at least 0.4 times the blade pitch diameter (D1);

a main motor (28 a) having a drive shaft (26 a); and

A drive gear (24 a) mechanically connected to the drive shaft (26 a), wherein the driven gear (22) and the drive gear (24 a) define a single stage transmission gear (30 a), wherein the transmission ratio is between 5:1 and 15:1.

2. Propeller (1) according to claim 1, wherein the driven ring (18) is a radially inner ring and the driven gear (22) is provided on a radially inner surface of the slew bearing (16).

3. Propeller (1) according to claim 2, wherein the drive gear (24 a) is positioned radially inside the slew bearing (16).

4. A propeller (1) according to any preceding claim, wherein the driven ring (18) and the driven gear (22) are formed as separate members that are fixed together to define an integral driven member of the slew bearing (16).

5. A propeller (1) according to any preceding claim, wherein the drive shaft (26 a) is substantially parallel to the rotational axis of the rotary housing (2).

6. A propeller as claimed in any preceding claim, wherein the drive gear is mechanically connected to the drive shaft by a main drive train, the main drive train including a mechanism for selectively disengaging the drive shaft from the driven ring.

7. The propeller of claim 6, wherein the mechanism is a clutch mechanism between the drive shaft and the drive gear.

8. Propeller (1) according to any one of the preceding claims, wherein the main electric motor (28 a) is a liquid-cooled permanent magnet motor.

9. The propeller (1) according to any one of the preceding claims, the propeller (1) further comprising a second main motor (28 b) having a second drive shaft (26 b), and a second drive gear (24 b) mechanically connected to the second drive shaft (26 b), wherein the driven gear (22) and the second drive gear (24 b) define a second single stage transmission gear (30 b).

10. The propeller (1) according to any preceding claim, the propeller (1) further comprising a plurality of blade actuators (8), each blade actuator (8) being mechanically connected to a respective one of the blades (4 a,4b, 4 f) for pivoting the blade about the blade axis.

11. Propeller (1) according to claim 10, wherein each blade actuator (8) comprises an electric motor (10).

12. The propeller (1) according to claim 11, the propeller (1) further comprising:

An auxiliary motor (32) for driving rotation of the rotary housing (2);

a main power supply; and

An auxiliary power supply;

wherein the main motor (28 a) is electrically connected to the main power source and the auxiliary motor (32) is electrically connected to at least one of the blade actuator motors (10) and configured to receive electrical power recovered by the at least one blade actuator motor (10) during a regeneration mode.

13. Propeller (1) according to claim 12, wherein the auxiliary motor (32) is fixed to a stationary part of the propeller (1).

14. The propeller of claim 12, wherein the auxiliary motor is fixed to the rotating housing.

15. The propeller (1) according to any preceding claim, wherein the plurality of blades (4 a,4b,..4 f) extend from a surface (2 a) of the rotating housing (2), and wherein the propeller (1) further comprises a first empty access volume (48 a) extending axially from a first access opening (46) in the surface (2 a) of the rotating housing (2) to a second access opening (50) adjacent to the swivel bearing (16), the first access opening (46) in the surface (2 a) of the rotating housing (2) being covered by a first removable access panel (44).

16. The propeller (1) according to claim 15, wherein the first empty entry volume (48 a) and the first and second entry openings (46, 50) are sized and shaped to fully receive the main motor (28 a) therethrough.

17. The propeller (1) according to claim 15 and claim 16, the propeller (1) further comprising a mounting plate (14) rotatably mounting the rotary housing (2) to the hull of the vessel, wherein the propeller (1) further comprises a second empty intake volume (48 b) extending axially from the second intake opening (50) to a third intake opening (42) in the mounting plate (14), and wherein the second empty intake volume (48 b) and the third intake opening (46) are sized and shaped to fully receive the main motor (28 a) therethrough.

18. The propeller (1) according to claim 17, wherein the third access opening (42) is covered by a second removable access panel (38).

19. The propeller (1) according to any one of claims 1 to 16, the propeller (1) further comprising a mounting plate (14) rotatably mounting the rotary housing (2) to the hull of the vessel, wherein the stationary ring (20) of the swivel bearing (16) is fixed to the mounting plate (14).

20. A propeller (1) according to any preceding claim, the propeller (1) being adapted to be mounted into the hull of the vessel from below.

21. Vessel comprising at least one propeller (1) according to any one of the preceding claims.

22. A method of operating a propeller (1) according to claim 11, the propeller further comprising an auxiliary motor (32) for driving the rotary housing (2), the method comprising supplying electrical power recovered by at least one of the vane actuator motors (10) during a regeneration mode to the auxiliary motor (32).

23. A method of operating a propeller (1) according to any one of claims 1 to 20 as a turbine, wherein the main motor (28 a) operates as a generator to generate electric power which is supplied to a main power supply electrically connected to the main motor (28 a).

24. A method of repairing or servicing a propeller (1) according to claim 16, wherein:

-said main motor (28 a) is separated from said propeller (1);

-removing the first access panel (44); and

The main motor (28 a) is fully received through the second access opening (50), the first access volume (48 a) and the first access opening (46).

25. A method of repairing or servicing a propeller (1) according to claim 18, wherein:

-said main motor (28 a) is separated from said propeller (1);

-removing the first access panel (44) and the second access panel (38); and

The main motor (28 a) is fully received through a third access opening (42), the second access volume (48 b), the second access opening (50), the first access volume (48 a), and the first access opening (46) in the mounting plate (14).