Patent Description:
The invention relates generally to cylcloidal-marine propulsion systems such as to flappin foil propulsors for marine vessels or the like.

Publication <CIT> presents a cycloidal marine-propulsion system. One problem with such cycloidal marine-propulsion system is that due to the relatively complex construction, mounting of a cycloidal marine-propulsion system to a ship and servicing of a cycloidal marine-propulsion system that is mounted to a ship is not easy.

Publication <CIT> presents a blade wheel propeller.

The object of the invention is to provide a marine propulsion unit that is easy to mount to a ship and that is easier to service.

The marine propulsion of the invention is characterized by the definitions of independent claim <NUM>.

Preferred embodiments of the marine propulsion are defined in the dependent claims <NUM> to <NUM>.

Claim <NUM> relates to a combination of a marine vessel and a marine propulsion unit according to any of the claims <NUM> to <NUM>.

In the following the invention will described in more detail by referring to the figures, which.

The figures show an embodiment of the marine propulsion unit.

The marine propulsion unit comprises a rotary casing <NUM> rotatable about a central axis A.

The marine propulsion unit comprises blades <NUM> extending axially from the rotary casing <NUM> for rotation with the rotary casing <NUM> about the central axis A. Each blade <NUM> is preferably, but not necessarily, mounted for pivotal movement about blade axes B generally parallel to the central axis A as illustrated in <FIG>.

A blade shaft portion <NUM> of each blade <NUM> is at least partly surrounded by a blade housing <NUM> and a blade portion <NUM> of each blade <NUM> is outside the blade housing <NUM>.

The blade housing <NUM> is releasable attached to the rotary casing <NUM>.

Each blade <NUM> is supported in the blade housing <NUM> by means of bearings 6a and 6b for said pivotal movement i.e. to make possible said pivotal movement.

In the marine propulsion unit, each blade <NUM> can together with a respective blade housing <NUM> be considered to form a blade unit (not marked with a reference numeral).

The marine propulsion unit provides for several advantages. The blade <NUM> that is supported in the blade housing <NUM> by means of the bearings 6a and 6b provides for a clear spare part package. The blade <NUM> that is supported in the blade housing <NUM> by means of the bearings 6a and 6b provides for a pre-assembled module that can be tested and be approved for example by classification societies prior mounting the blade <NUM> to the rotary casing <NUM> of the marine propulsion unit. Mounting of the blades <NUM> to the rotary casing <NUM> is easy: Because the blade shaft portion <NUM> of the blade <NUM> is already fitted into the bearings 6a and 6b for example at a factory, the blade shaft portion <NUM> of the blade <NUM> need not to be fitted into the bearings 6a and 6b simultaneously when mounting the blade <NUM> to the rotary casing <NUM> for example at a shipyard. This also makes servicing and replacing of individual blades easy. This is an advantage, because the blades <NUM> can be <NUM> to <NUM> meters long. The risk that the bearings 6a and 6b are damaged is consequently reduced.

The marine propulsion unit comprises preferably, but not necessarily, a retaining arrangement (not shown in the figures) for keeping the blade shaft portion <NUM> of each blade <NUM> in a respective blade housing. Said retaining arrangement can for example comprise at least one of a wedge connection, a shrink connection, a retaining screw and a retaining ring.

The blades <NUM> are preferably, but not necessarily, evenly distributed at the rotary casing <NUM> with respect to the central axis A.

The rotary casing <NUM> of the marine propulsion unit comprises preferably, but not necessarily, a lower surface <NUM> that is configured to be at least partly in direct contact with water. The lower surface <NUM> can be flat as shown in the figures.

If the rotary casing <NUM> comprises such lower surface <NUM>, the rotary casing <NUM> comprises preferably, but not necessarily, mounting seats <NUM> configured to releasable receive the blade housing <NUM> of each blade <NUM> such that the mounting seats <NUM> extend from the lower surface <NUM> of the rotary casing <NUM> into the rotary casing <NUM> and form apertures in the rotary casing <NUM>. Alternatively, at least one mounting seat <NUM> can extend from the lower surface <NUM> of the rotary casing <NUM> into the rotary casing <NUM> so that said at least one mounting seat <NUM> form a recess in the rotary casing <NUM>.

If the rotary casing <NUM> comprises such mounting seats, the blade housing <NUM> has preferably, but not necessarily, an outer surface <NUM>, which can be a circumferential outer surface, as in <FIG>, and the mounting seat <NUM> has preferably, but not necessarily, an inner surface <NUM>, which can be a circumferential inner surface, as in <FIG>, such that the outer surface <NUM> of the blade housing <NUM> at least partly abuts the inner surface <NUM> of the mounting seat <NUM> so as to prevent lateral movement of the blade housing <NUM> in the mounting seat <NUM>. The inner surface <NUM> together with the outer surface <NUM> also functions as steering surfaces when mounting the blade housing <NUM> together with the blade <NUM> at the rotary casing <NUM>.

If the rotary casing <NUM> comprises such mounting seats <NUM>, the blade housing <NUM> has preferably, but not necessarily, a first section (not marked with a reference numeral) where the cross-section form and the outer dimensions of the blade housing <NUM> corresponds to the cross-section form and inner dimensions of a second section (not marked with a reference numeral) of the mounting seat <NUM> so as to prevent lateral movement of the blade housing <NUM> in the mounting seat <NUM>. The first section together with the second section also functions as steering surfaces when mounting the blade housing <NUM> together with the blade <NUM> at the rotary casing <NUM>.

Such first section of the blade housing <NUM> is preferably, but not necessarily, formed by a circumferential outer surface of the blade housing <NUM> that has an outer diameter that essentially corresponds to the inner diameter of a second section of the mounting seat <NUM> in the form of a circumferential inner surface of the mounting seat <NUM> extending from a lower surface <NUM> of the rotary casing <NUM> so as to prevent lateral movement of the blade housing <NUM> in the mounting seat <NUM>.

If the rotary casing <NUM> comprises such mounting seats <NUM>, the blade housing <NUM> can comprise a first lower flange <NUM> having an upper surrounding surface <NUM> configured to abut a lower surrounding surface <NUM> of a second lower flange <NUM> that surrounds the mounting seat <NUM> when the blade housing <NUM> is brought into a mounting position in the mounting seat <NUM> from the side of the lower surface <NUM> of the rotary casing <NUM>.

If the rotary casing <NUM> comprises such mounting seats <NUM>, the mounting seats <NUM> are preferably, but not necessarily, designed and dimensioned to allow inserting and removal of a blade housing <NUM> having a blade <NUM> supported in the blade housing <NUM> by means of bearings 6a and 6b solely from the side of lower surface <NUM> of the rotary casing <NUM>. In other words, the so-called pre-assembled module comprising a blade housing <NUM> having a blade <NUM> supported in the blade housing <NUM> by means of bearings 6a and 6b is preferably, but now necessarily, solely insertable and removable from a mounting sear extending from the lower surface of the rotary casing from the side of lower surface <NUM> of the rotary casing <NUM>. This means that the so-called pre-assembled module can be inserted and removed from the rotary casing <NUM> without disconnecting the rotary casing for example from the hull <NUM> of a ship to which the rotary casing <NUM> is mounted.

In the second embodiment of the marine propulsion unit shown in <FIG>, the third embodiment of the marine propulsion unit shown in <FIG>, and in the fourth embodiment of the marine propulsion unit shown in <FIG>, the rotary casing <NUM> comprises a central portion <NUM>, each blade housing <NUM> comprises a first lateral attachment member <NUM>, and each blade housing <NUM> is releasable attached to the central portion <NUM> of the rotary casing <NUM> so that the first lateral attachment member <NUM> of each blade housing <NUM> is attached to corresponding second lateral attachment member <NUM> provided laterally at the central portion <NUM> of the rotary casing <NUM>. The first lateral attachment members <NUM> can be planar as shown in the figures. The second lateral attachment members <NUM> can be planar as shown in the figures. A first lateral attachment member <NUM> of a blade housing <NUM> can for example be attached to a second lateral attachment member <NUM> provided laterally at the central portion <NUM> of the rotary casing <NUM> by using external fastening means (not illustrated in the figures) once the first lateral attachment member <NUM> of a blade housing <NUM> is brought into contact with a second lateral attachment member <NUM> provided laterally at the central portion <NUM> of the rotary casing <NUM>. More precisely, as shown in <FIG>, <FIG>, <FIG> and <FIG>, this is done by moving such as lifting the blade housing <NUM> having a blade <NUM> supported in the blade housing <NUM> by means of bearings 6a and 6b in relation to the rotary casing <NUM> so that the first lateral attachment member <NUM> of a blade housing <NUM> is brought into contact with a second lateral attachment member <NUM> provided laterally at the central portion <NUM> of the rotary casing <NUM>, whereafter external fastening means are used for releasable fasten the first lateral attachment member <NUM> of a blade housing <NUM> to the second lateral attachment member <NUM> provided laterally at the central portion <NUM> of the rotary casing <NUM>.

In the third embodiment of the marine propulsion unit shown in <FIG>, and in the fourth embodiment of the marine propulsion unit shown in <FIG> the rotary casing <NUM> comprises an outer casing <NUM> surrounding the central portion <NUM> or the rotary casing <NUM>, the outer casing comprises mounting seats <NUM> configured to releasable receive the blade housing <NUM> of each blade <NUM>, and the mounting seats <NUM> extend from a lower outer surface <NUM> of the outer casing <NUM> of the rotary casing <NUM>. One purpose of the outer casing is to improve the hydrodynamic characteristics of the marine propulsion unit by creating a smooth design with less edges, cavities and protrusions and the like.

In the third embodiment of the marine propulsion unit shown in <FIG>, and in the fourth embodiment of the marine propulsion unit shown in <FIG> the outer casing <NUM> of the rotary casing <NUM> is composed of several outer casing sections <NUM> separated by division planes <NUM> dividing each mounting seat <NUM> in the outer casing in at least two mounting seat sections (not marked with a reference numeral) so the each adjacent outer casing sections <NUM> of the outer casing <NUM> comprises a mounting seat section of at least one mounting seat <NUM>.

In the in the third embodiment of the marine propulsion unit shown in <FIG> the mounting seats <NUM> in the outer casing <NUM> of the rotary casing <NUM> is designed and dimensioned so that outer casing sections <NUM> must be removed to allow inserting and removal of a blade housing <NUM> having a blade <NUM> supported in the blade housing by means of bearings 6a and 6b. Because the outer casing <NUM> is divided by division planes <NUM> into several outer casing sections <NUM>, only some outer casing sections <NUM> and not the complete outer casing <NUM> needs to be removed to allow inserting and removal of a blade housing <NUM> having a blade <NUM> supported in the blade housing by means of bearings 6a and 6b.

In the in the fourth embodiment of the marine propulsion unit shown in <FIG> the mounting seats <NUM> in the outer casing <NUM> of the rotary casing <NUM> is designed and dimensioned to allow inserting and removal of a blade housing <NUM> having a blade <NUM> supported in the blade housing by means of bearings 6a and 6b solely from the side of lower outer surface <NUM> of the outer casing <NUM> of the rotary casing <NUM> and without removing outer casing sections <NUM>. In other words, in the fourth embodiment of the marine propulsion unit shown in <FIG>, a blade housing <NUM> having a blade <NUM> supported in the blade housing by means of bearings 6a and 6b can moved such as lifted up into a mounting seat <NUM> extending from the lower surface <NUM> of the outer casing <NUM> and correspondingly be lowered from a mounting seat <NUM> extending from the lower surface <NUM> of the outer casing <NUM> without removing outer casing sections <NUM>. In the in the fourth embodiment of the marine propulsion unit shown in <FIG> the mounting seats <NUM> extending from the lower surface <NUM> of the outer casing <NUM> are preferably, but not necessarily, designed to that the mounting seats <NUM> are configured to steer the first lateral attachment member <NUM> of a blade housing <NUM> into contact with a second lateral attachment member <NUM> provided laterally at the central portion <NUM> of the rotary casing <NUM> when blade housing <NUM> having a blade <NUM> supported in the blade housing by means of bearings 6a and 6b is moved into the mounting seat <NUM>.

If the marine propulsion unit comprises first lateral attachment members <NUM> at the blade housings and second lateral attachment members <NUM> at a central potion <NUM> of the rotary casing <NUM>, electrical power and/or steering signal connectors (not illustrated in the figures) can also be provided in connection with such first lateral attachment members <NUM> at the blade housings and second lateral attachment members <NUM> at a central potion <NUM> of the rotary casing <NUM> so that optional electrical power and/or steering signal connections between the blade housing <NUM> having a blade <NUM> supported in the blade housing by means of bearings 6a and 6b and other parts of the marine propulsion unit can easily be formed in connection with releasable fastening the first lateral attachment member <NUM> of a blade housing <NUM> to the second lateral attachment member <NUM> provided laterally at the central portion <NUM> of the rotary casing <NUM>.

If the marine propulsion unit comprises first lateral attachment members <NUM> at the blade housings and second lateral attachment members <NUM> at a central potion <NUM> of the rotary casing <NUM>, the rotary casing <NUM> has preferably, but not necessarily, as illustrated in <FIG> and <FIG>, a hollow interior <NUM>, and the first lateral attachment member <NUM> of each blade housing <NUM> are preferably, but not necessarily releasable attached to a corresponding second lateral attachment member <NUM> provided laterally at the central portion <NUM> of the rotary casing <NUM> by means of fastening means extending from the hollow interior <NUM> of the rotary casing <NUM> into the first lateral attachment member <NUM> of each blade housing <NUM> as illustrated in <FIG> and <FIG>. Such fastening allows for easy of attachment of the blade housings <NUM> to and detaching of the blade housings <NUM> from the central portion <NUM> of the rotary casing <NUM>. It is for example possible that threaded holes <NUM> in the first lateral attachment member <NUM> of each blade housing <NUM> are aligned with holes <NUM> at said corresponding second lateral attachment member <NUM> provided laterally at the central portion <NUM> of the rotary casing <NUM>, and that the fastening means comprises bolts <NUM> screwed into the threaded holes <NUM> in the first lateral attachment member <NUM> of each blade housing <NUM> from the hollow interior <NUM> of the rotary casing <NUM> so that the heads of each bolt <NUM> are at least partly inside the hollow interior <NUM> of the rotary casing <NUM>.

The marine propulsion unit comprises preferably, but not necessarily, a mounting body <NUM>, configured to attach the marine propulsion unit to a marine vessel or the like such as to a ship, preferably to the hull <NUM> of a ship, wherein the rotary casing <NUM> is rotatable mounted at said mounting body <NUM> for said rotation about the central axis A. The marine propulsion unit comprises preferably, but not necessarily, a mounting body <NUM>, configured to attach the marine propulsion unit to a marine vessel or the like such as to a ship, preferably to the hull <NUM> of a ship, wherein the rotary casing <NUM> is rotatable mounted at said mounting body <NUM> for said rotation about the central axis A, and the rotary casing <NUM> comprises preferably, but not necessarily, having a hollow interior <NUM>, and the marine propulsion unit is preferably, but not necessarily, provided with a manhole arrangement <NUM> for providing access to the hollow interior <NUM> of the rotary casing <NUM> so that the manhole arrangement <NUM> leads through the mounting body <NUM> into the hollow interior <NUM> of the rotary casing <NUM>, as illustrated in <FIG>, <FIG> and <FIG>. The marine propulsion unit comprises preferably, but not necessarily, a rotating means <NUM> configured to rotate the rotary casing <NUM> with respect to the mounting body <NUM>. The rotating means <NUM> can comprise one of an electric motor, as in the embodiment illustrated in <FIG>, <FIG>, and <FIG> a hydraulic arrangement, and a mechanical arrangement or a combination thereof.

The bearings for supporting the blades in the blade housings <NUM> comprise preferably, but not necessarily, a first bearing 6a and a second bearing 6b. The first bearing 6a is provided inside the blade housing <NUM> at a first end (not marked with a reference numeral) of the blade shaft portion <NUM> of the blade <NUM> and the second bearing 6b is provided inside the blade housing <NUM> at the opposite second end (not marked with a reference numeral) of the blade shaft portion <NUM> of the blade <NUM>. An advantage of this is that the first bearing 6a and the second bearing 6b will as far from each other as possible and this provides for a stable supporting of the blades <NUM> in the blade housings <NUM>.

If the bearings for supporting the blades in the blade housings <NUM> comprise a first bearing 6a and a second bearing 6b as described, the first bearing 6a is preferably, but not necessarily, a cylindrical bearing or a roller bearing. One purpose of the first bearing 6a is to transmit radial forces from the blade <NUM> to the rotary casing <NUM> via the blade housing <NUM>.

If the bearings for supporting the blades in the blade housings <NUM> comprise a first bearing 6a and a second bearing 6b as described, a first seal arrangement <NUM> is preferably, but not necessarily, provided between the blade shaft portion <NUM> of the blade <NUM> and the blade housing <NUM> at the first bearing 6a on the side of the first bearing 6a that faces the second bearing 6b. One purpose of the first seal arrangement <NUM> is to prevent lubrication from leaking from the first bearing 6a.

If the bearings for supporting the blades in the blade housings <NUM> comprise a first bearing 6a and a second bearing 6b as described, the second bearing 6b is preferably, but not necessarily, a spherical roller bearing. The spherical roller bearing transmits axial and radial forces from the blade <NUM> to the rotary casing <NUM> via the blade housing <NUM>.

If the bearings for supporting the blades <NUM> in the blade housings <NUM> comprise a first bearing 6a and a second bearing 6b as described, a second seal arrangement <NUM> is preferably, but not necessarily, between the blade shaft portion <NUM> of the blade <NUM> and the blade housing <NUM> at the second bearing 6b on the side of the second bearing 6b that faces the blade portion <NUM> of the blade <NUM>. One purpose of the second seal arrangement <NUM> is to protect the second bearing against water that at least partly surrounds the blade portion <NUM> of the blade <NUM>, when the marine propulsion unit is mounted at a marine vessel and when the marine vessel floats in water. Another purpose of the second seal arrangement <NUM> is to prevent lubrication from leaking from the second bearing 6a.

If the bearings for supporting the blades in the blade housings <NUM> comprise a first bearing 6a and a second bearing 6b as described, a third seal arrangement <NUM> is preferably, but not necessarily, between the blade shaft portion <NUM> of the blade <NUM> and the blade housing <NUM> at the second bearing 6b on the side of the second bearing 6b that faces the first bearing 6a. One purpose of the third seal arrangement <NUM> is to prevent lubrication from leaking from the second bearing 6a.

Each blade comprises preferably, but not necessarily, a pivoting means <NUM> functionally connected between the blade <NUM> and the blade housing <NUM>. The pivoting means <NUM> is configured to pivot the blade <NUM> with respect to the blade housing <NUM> for performing said pivotal movement of the blade <NUM> about blade axes B, which may be generally parallel to the central axis A. Each pivoting means <NUM> can comprise one of an electric motor, a hydraulic arrangement, and a mechanical arrangement or a combination thereof. Each pivoting means <NUM> is preferably, but not necessarily, independently operable. The blade portion <NUM> of each blade <NUM> comprises preferably, but not necessarily, an elongated leading edge <NUM> and an elongated trailing edge <NUM>, and by the marine propulsion unit comprises preferably, but not necessarily, a steering unit <NUM> configurable to control the pivoting means <NUM> so that the trailing edge <NUM> of the blade portion <NUM> of each blade <NUM> moves in an ordinary cycloid or curtate cycloid path when the marine propulsion unit moves linearly when propulsing a marine vessel to move the marine vessel linearly or along a curve when propulsing a marine vessel to move the marine vessel along a curve.

If each blade <NUM> comprises a pivoting means <NUM>, as described, the blade housing <NUM> encapsulates preferably, but not necessarily, the pivoting means <NUM>. An advantage of this is that the blade housing <NUM> protects the pivoting means <NUM> during assembly at the rotary casing <NUM>. Another advantage is that the pivoting means <NUM> can be sealed in the blade housing <NUM> against water by means of the blade housing <NUM>. Another advantage of this is that this provides for an assembly-ready unit comprising both the blade <NUM> and the pivoting means <NUM> for pivoting the blade <NUM> with respect to the rotary casing <NUM>.

If each blade <NUM> of the marine propulsion unit comprise a first bearing 6a and a second bearing 6b as described, and if each blade of the marine propulsion unit comprise a pivoting means <NUM>, as described, the pivoting means <NUM> is preferably, but not necessarily, functionally connected to the blade shaft portion <NUM> of the blade <NUM> between the first bearing 6a and the second bearing 6b, as shown in <FIG>. In such case, each pivoting means <NUM> is preferably, but not necessarily, an electric motor (not marked with a reference numeral), wherein the electric motor surrounds the blade shaft portion <NUM> of the blade <NUM> in the blade housing <NUM>. If each pivoting means <NUM> is an electric motor, the stator <NUM> of the electric motor is preferably, but not necessarily, attached to the blade housing <NUM>, and the rotor <NUM> of the electric motor is preferably, but not necessarily, attached to the blade shaft portion <NUM> of the blade <NUM>, as shown in <FIG>.

Each blade housing <NUM> comprise preferably, but not necessarily, at least one bolt flange <NUM> at the blade housing <NUM>, wherein the bolt flange <NUM> is configured to co-operate with fastening means <NUM>, such as with a co-operating bolt flange, at the rotary casing <NUM> for releasable attaching the blade housing <NUM> to the rotary casing <NUM>.

Each blade housing <NUM> can for example comprise, as shown in the figures, a bolt flange <NUM> at one end of the blade housing <NUM>, wherein the bolt flange <NUM> is configured to co-operate with fastening means <NUM>, such as with a co-operating bolt flange, at the rotary casing <NUM> for releasable attaching the blade housing <NUM> to the rotary casing <NUM>.

The rotary casing <NUM> of the marine propulsion unit has preferably, but not necessarily, a hollow interior <NUM>, and the marine propulsion unit is preferably, but not necessarily provided with a manhole arrangement <NUM> for providing access to the hollow <NUM> interior of the rotary casing <NUM> as illustrated in <FIG>, <FIG> and <FIG>. Such manhole arrangement <NUM> is preferably, but not necessarily, configured to provide a passage between the hollow interior <NUM> of the rotary casing <NUM> and the marine vessel.

Claim 1:
Marine propulsion unit comprising
a rotary casing (<NUM>) rotatable about a central axis A, and
blades (<NUM>) extending axially from the rotary casing (<NUM>) for rotation with the rotary casing (<NUM>) about the central axis A, wherein each blade (<NUM>) is mounted for pivotal movement about blade axes B,
a blade shaft portion (<NUM>) of each blade (<NUM>), which is at least partly surrounded by a blade housing (<NUM>) and a blade portion (<NUM>) of each blade (<NUM>) is outside the blade housing (<NUM>), wherein the blade housing (<NUM>) is releasable attached to the rotary casing (<NUM>) and wherein each blade (<NUM>) is supported in the blade housing (<NUM>) by means of bearings (6a and 6b) for said pivotal movement, wherein the rotary casing (<NUM>) comprises a lower surface (<NUM>) that is configured to be in direct contact with water, wherein the rotary casing (<NUM>) comprises mounting seats (<NUM>) configured to releasably receive the blade housing (<NUM>) of each blade (<NUM>), wherein the mounting seats (<NUM>) extend from the lower surface (<NUM>) of the rotary casing (<NUM>) into the rotary casing (<NUM>) and form apertures or recesses in the rotary casing (<NUM>), where the blade housing (<NUM>) has an outer surface (<NUM>) and the mounting seats (<NUM>) have an inner surface (<NUM>), the inner surface (<NUM>) together with the outer surface functions as steering surfaces when mounting the blade housing (<NUM>) together with the blade (<NUM>) at the rotary casing (<NUM>), characterised in that the mounting seats (<NUM>) are designed and dimensioned to allow inserting and removal of a pre-assembled module formed by the blade housing (<NUM>) having a blade (<NUM>) supported in the blade housing (<NUM>) by means of bearings (6a and 6b), solely from the side of lower surface (<NUM>) of the rotary casing (<NUM>). [end of claim <NUM>, text before claim <NUM> can be deleted] casing (<NUM>), and
by the blade housing (<NUM>) has an outer surface (<NUM>) and the mounting seat (<NUM>) has an inner surface (<NUM>), the inner surface (<NUM>) together with the outer surface functions as steering surfaces when mounting the blade housing (<NUM>) together with the blade (<NUM>) at the rotary casing (<NUM>).