WATER VEHICLE HAVING A CRANE FOR LIFTING LOADS

Abstract

A watercraft may include a crane for lifting loads. The crane may include a tower and a boom that is rotatble with respect to the tower. The tower may be positioned inside the outer contour of the watercraft so as to minimize the profile of the watercraft on radar. The watercraft may include a superstructure within which the tower may be disposed. The superstructure may include planar outer walls that are obtuse relative to a horizontal plane. A rotary bearing may be utilized to connect the boom to the tower and permit the boom to rotate relative to the tower. Further, when the boom is in a rest position, a lower edge of the boom may be positioned 10 cm or less above the crane deck.”

Claims

1.-16. (canceled)

17. A watercraft comprising a crane for lifting loads, wherein the crane comprises a tower and a boom that is rotatable with respect to the tower, wherein the tower is disposed inside an outer contour of the watercraft.

18. The watercraft of claim 17 further comprising a superstructure, wherein the tower is disposed inside the superstructure.

19. The watercraft of claim 17 wherein outer walls of the superstructure are planar and have an obtuse angle with respect to a horizontal plane.

20. The watercraft of claim 17 further comprising a rotary bearing that connects the boom to the tower, wherein the rotary bearing is disposed inside the outer contour of the watercraft.

21. The watercraft of claim 17 wherein the boom is movable into a rest position in which the boom is disposed above a crane deck of the watercraft such that a distance between a lower edge of the boom and the crane deck is less than 10 cm.

22. The watercraft of claim 21 wherein in the rest position at least one of: a side wall of the boom encloses an obtuse angle with the crane deck, or a side wall of the boom forms a continuation of a suitable surface of the outer contour of the watercraft.

23. The watercraft of claim 17 wherein the boom is movable into a use position in which a free end of the boom projects laterally beyond an edge of a crane deck of the watercraft.

24. The watercraft of claim 23 wherein in the use position a distance of the boom from a main deck of the watercraft is in a range of 1 to 3 deck heights.

25. The watercraft of claim 17 wherein the boom is configured in a rod shape.

26. The watercraft of claim 17 wherein the boom is disposed substantially at a right angle to a longitudinal axis of the tower.

27. The watercraft of claim 17 wherein the boom is telescopic.

28. The watercraft of claim 17 wherein the crane comprises a crane hook that is movable into a position in which the crane hook is disposed within the boom.

29. The watercraft of claim 17 wherein the tower is telescopic.

30. The watercraft of claim 17 wherein the tower comprises a sea-swell-following device for compensating for a sea-swell-induced movement of a cable-suspension point of the crane.

31. The watercraft of claim 17 wherein the crane comprises at least one of a cable winch or a hydraulic assembly disposed inside the outer contour of the watercraft.

32. The watercraft of claim 17 wherein the crane is remote controllable.

33. The watercraft of claim 17 wherein the crane is a first crane, the watercraft further comprising a second crane.

34. The watercraft of claim 17 wherein the tower is disposed below a crane deck.

35. The watercraft of claim 17 wherein the boom is movable into a rest position in which the boom is disposed above a crane deck of the watercraft such that a distance between a lower edge of the boom and the crane deck is less than 1 cm.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0022] FIG. 1 shows a first watercraft with a crane for lifting loads in a perspective illustration, wherein the crane is in a position of rest.

[0023] FIG. 2 shows a second watercraft with a crane for lifting loads in a plan view, wherein the crane is in a position of rest.

[0024] FIG. 3 shows the watercraft from FIG. 2 in a plan view, wherein the crane is in a first position of use.

[0025] FIG. 4 shows the watercraft from FIG. 2 in a plan view, wherein the crane is in a second position of use.

EMBODIMENTS OF THE INVENTION

[0026] In the various figures, identical parts are always provided with the same reference symbols and are therefore as a rule also each specified or mentioned only once.

[0027] FIG. 1 illustrates the stern of a watercraft 1 according to a first exemplary embodiment of the invention. The watercraft 1 is configured as a military sea vessel, for example as a corvette or patrol ship. In the region of the stern, the watercraft 1 has a main deck 4 which limits the hull 2 in the upward direction and which is used as a helicopter landing deck. A superstructure 3, which extends over a height of two decks and accommodates a hangar storing helicopters and other pieces of equipment, is arranged on the main deck 4. The superstructure is limited in the upward direction by a crane deck 7. The crane deck 7 therefore forms part of the outer contour of the watercraft 1.

[0028] A crane 16 embodied according to the prior art is provided on the starboard side, on an intermediate deck arranged between the main deck 4 and the crane deck 7. The crane is embodied as a loading crane which is permanently installed on the intermediate deck 7. In an out-of-use position shown in FIG. 1, the crane 16 rests in a retracted fashion on a bearing of a crane arm. As a result of the crane 16 resting on the intermediate deck, the radar cross section of the watercraft 1 is degraded significantly on the starboard side and from astern.

[0029] In order to make the radar cross section of the watercraft 1 smaller and therefore to reduce the possibility of the watercraft 1 being discovered by enemy radar, instead of the crane 16 known from the prior art it is possible to use a crane 10 according to the invention, which crane 10 is illustrated by way of example on the port side of the watercraft 1. The crane 10 can be provided in a form which differs from the exemplary embodiment on the starboard side. According to a further refinement, the watercraft 1 can have two cranes, for example a crane on the port side and a crane on the starboard side, respectively.

[0030] The crane 10 has a tower 11 and a boom 13 which can rotate with respect to the tower 11. The tower 11 of the crane 10 is arranged inside the outer contour of the watercraft 1, with the result that the radar radiation which is emitted by a radar device is reflected by the outer contour of the watercraft 1, here the surface of the superstructure 3, and cannot impinge on the tower 11. The contribution of the tower 11 to the radar cross section of the watercraft 1 is therefore eliminated, and the radar cross section is reduced overall. In the exemplary embodiment, the tower 11 is arranged within the superstructure 3. The superstructure 3 can be configured in the manner of a cloaking device and have a radar cross section which is reduced compared to conventional superstructures. This can be achieved, for example, by virtue of the fact that the outer walls of the superstructure 3 are of planar design and have an obtuse angle with respect to the horizontal.

[0031] The crane 10 is embodied as a revolving tower crane which is integrated into the superstructure 3 and whose tower 11 is arranged completely below the crane deck 7. The boom 13 of the crane 10 is rigidly connected to a rotary bearing 12 which is embodied as a live ring, with the result that the boom 13 can be rotated about the longitudinal axis of the tower 11, but there is no degree of freedom about a rotational axis transversely, in particular perpendicularly, with respect to the longitudinal axis of the tower 11. In the exemplary embodiment, the rotary bearing 12 is arranged together with the tower 11 inside the outer contour of the watercraft 1 and therefore does not contribute to the radar cross section of the watercraft 1. The rotary bearing 12 terminates flush with the upper edge of the superstructure 3, that is to say the crane deck 7.

[0032] In the illustration according to FIG. 1 the boom 13 of the crane 10 is in a position of rest in which the boom 13 is arranged above the crane deck 7, and the distance between the lower edge of the boom 13 and the crane deck 7 is as short as possible. The boom 13 can rest directly on the crane deck 7 or alternatively rest on thin sliding bearings which are mounted on the crane deck 7. According to the exemplary embodiment, the distance is less than 10 cm, preferably less than 5 cm, particularly preferably less than 1 cm. The boom 12 is embodied overall in the manner of a rod which extends from the rotary bearing 12 along a straight line which encloses a right angle with the longitudinal axis of the tower 11. The side walls of the boom 13 enclose, in the position of use, an obtuse angle with the surface of the crane deck 7. In the exemplary embodiment, the boom 13 in the position of rest is arranged in a position transversely, in particular at a right angle, with respect to the longitudinal axis of the watercraft 1. Alternatively, the boom 13 in the position of rest can be arranged parallel to the longitudinal axis of the watercraft 1.

[0033] A cable winch 14 and a hydraulic assembly (not illustrated) are also arranged within the superstructure 3. The crane 10 is remote-controllable, with the result that members of the crew for operating the crane 10 can assume an optimum position.

[0034] The illustrations in FIGS. 2, 3 and 4 show a second exemplary embodiment of the invention. In FIG. 2, the crane 10 is in the position of rest. In FIGS. 3 and 4, the crane assumes two different positions of use, wherein the free end 13.3 of the boom 13 projects laterally beyond the edge of the crane deck. In the position of use according to FIG. 2, the boom is arranged at a distance of approximately 5 m above the main deck 4. This height is sufficient for loading helicopters, drones, transport containers, boats and other loads between the watercraft 1 and the land, with the result that it is not necessary to top the crane. FIG. 3 shows the crane 10 when picking up a load 15 from a land vehicle 8 which is located on a quay wall 9.

[0035] In one refinement of the exemplary embodiment described above, the crane 10 can have a sea-swell-following device by means of which sea-swell-induced movements of the cable-suspension point of the crane 10 can be compensated for. The sea-swell-following device can be integrated in the tower 11.

[0036] The watercraft 1 described above have a crane 10 for lifting loads, which crane 10 has a tower 11 and a boom 13 which can rotate with respect to the tower 11, wherein the tower 11 is arranged inside the outer contour of the watercraft 1.

LIST OF REFERENCE NUMBERS

[0037] 1 Watercraft [0038] 2 Hull [0039] 3 Superstructure [0040] 4 Main deck [0041] 5 Intermediate deck [0042] 6 Hangar [0043] 7 Crane deck [0044] 8 Land vehicle [0045] 9 Quay wall [0046] 10 Crane [0047] 11 Tower [0048] 12 Live ring [0049] 13 Boom [0050] 13.2, 13.2 Boom segment [0051] 13.3 Free end [0052] 14 Cable winch [0053] 15 Load [0054] 16 Crane