Marine knuckle boom crane

Patent metadata

Field	Value
Publication number	US-9809429-B2
Application number	US-201314409329-A
Country	US
Kind code	B2
Filing date	Jul 8, 2013
Priority date	Jul 16, 2012
Publication date	Nov 7, 2017
Grant date	Nov 7, 2017

Abstract

A marine knuckle boom crane includes a crane housing which is rotational relative to a pedestal about a vertical rotation axis and a knuckle boom assembly attached to the crane housing. The knuckle boom assembly includes a main boom, the inner end of which is connected pivotably about a first horizontal pivot axis to the crane housing; and a jib, the inner end of which is connected pivotably about a second horizontal pivot axis to the outer end of the main boom, wherein the jib is pivotable at least between an extended position in which the tip extends mainly forward from the main boom, and a folded position in which the jib is folded back, essentially parallel along the main boom. In order to position the jib with respect to the main boom, a tensioning member is provided extending between the crane housing and a curved extension guide connected to the jib.

First claim

The invention claimed is:

1. A marine knuckle boom crane comprising:
a stationary pedestal to be mounted to or formed integral with a vessel;
a crane housing having an upper portion, a central portion and a lower portion, the crane housing being rotational relative to the pedestal about a vertical rotation axis; and
a knuckle boom assembly attached to the crane housing, the knuckle boom assembly comprising:
a main boom comprising an inner end, a central area and an outer end, the inner end of the main boom being connected pivotably about a first horizontal pivot axis to a lower portion of the crane housing;
a jib comprising an inner end, a central area and a tip opposite the inner end of the jib, the inner end of the jib being connected pivotably about a second horizontal pivot axis to the outer end of the main boom, wherein the jib is pivotable at least between an extended position in which the tip extends mainly forward from the main boom, and a folded position in which the jib is folded back, with the tip of the jib being brought to be close to a middle portion of the main boom;
a tensioning member and a curved extension guide for positioning the jib with respect to the main boom, the tensioning member extending between the crane housing and the curved extension guide,
wherein the tensioning member comprises:
a first portion comprising at least two articulated interconnected elongated rods; and
a second portion comprising sheaves and a cable, a length of the cable being variable, one of the at least two articulated interconnected elongated rods being connected to the second portion via a first pivot point, the at least two articulated interconnected elongated rods being interconnected via a second pivot point, and

wherein the curved extension guide is mounted to the jib, pivotable together with the jib about the second pivot axis, and comprises:
three spokes including a first spoke, a second spoke and a third spoke, each having a distal end;
a connecting beam extending from the third spoke to the tip of the jib,
wherein the tensioning member is connected to the third spoke, and the first and second pivot points of the tensioning member are adapted to coincide with the distal ends of the first and second spokes of the curved extension guide, respectively, and
wherein:
when the jib is in the folded position, the first portion of the tensioning member is guided by the curved extension guide, and the first and second pivot points of the tensioning member coincide with the distal ends of the first and second spokes of the curved extension guide, respectively,
when the jib is in the extended position, the first pivot point is spaced apart from the distal end of the first spoke by a distance, with the distal end of the first spoke being a free end, and the second pivot point is spaced apart from the distal end of the second spoke by a distance, with the distal end of the second spoke being a free end, and
when the jib is in an intermediate position between the folded position and the extended position, the first pivot point is spaced apart from the distal end of the first spoke by a distance, with the distal end of the first spoke being a free end, and the second pivot point coincides with the distal end of the second spoke;

a tensioning winch configured to vary the length of the cable of the tensioning member and thus to position the jib;
a luffing cable for positioning the main boom, extending between the outer end of the main boom and the upper portion of the crane housing; and
a luffing winch configured to vary the length of the luffing cable and thus to position the main boom.

2. The marine knuckle boom crane according to claim 1 , wherein a yang is provided between the main boom and the jib to position and/or fixate the position of the jib with respect to the main boom.

3. The marine knuckle boom crane according to claim 2 , wherein the tensioning member extends between the lower portion of the crane housing and the curved extension guide.

4. The marine knuckle boom crane according to claim 2 , wherein the tensioning member extends between the central portion of the crane housing and the curved extension guide.

5. The marine knuckle boom crane according to claim 2 , wherein the tensioning member extends between the upper portion of the crane housing and the curved extension guide.

6. The marine knuckle boom crane according to claim 2 , wherein the tensioning member comprises a first portion being guided by the curved extension guide and a second portion of which the length may be varied by the tensioning winch.

7. The marine knuckle boom crane according to claim 2 , further comprising a hoist assembly, comprising a hoist winch and a hoisting cable, extending from the hoist winch via sheaves over the tip of the jib to a load suspension device.

8. The marine knuckle boom crane according to claim 1 , wherein the tensioning member extends between the lower portion of the crane housing and the curved extension guide.

9. The marine knuckle boom crane according to claim 8 , wherein the tensioning member comprises a first portion being guided by the curved extension guide and a second portion of which the length may be varied by the tensioning winch.

10. The marine knuckle boom crane according to claim 8 , further comprising a hoist assembly, comprising a hoist winch and a hoisting cable, extending from the hoist winch via sheaves over the tip of the jib to a load suspension device.

11. The marine knuckle boom crane according to claim 1 , wherein the tensioning member extends between the central portion of the crane housing and the curved extension guide.

12. The marine knuckle boom crane according to claim 11 , wherein the length of the cable of the second portion is varied by the tensioning winch.

13. The marine knuckle boom crane according to claim 11 , further comprising a hoist assembly, comprising a hoist winch and a hoisting cable, extending from the hoist winch via sheaves over the tip of the jib to a load suspension device.

14. The marine knuckle boom crane according to claim 1 , wherein the tensioning member extends between the upper portion of the crane housing and the curved extension guide.

15. The marine knuckle boom crane according to claim 14 , wherein the tensioning member comprises a first portion being guided by the curved extension guide and a second portion of which the length may be varied by the tensioning winch.

16. The marine knuckle boom crane according to claim 14 , further comprising a hoist assembly, comprising a hoist winch and a hoisting cable, extending from the hoist winch via sheaves over the tip of the jib to a load suspension device.

17. The marine knuckle boom crane according to claim 1 , wherein the length of the cable of the second portion is varied by the tensioning winch.

18. The marine knuckle boom crane according to claim 17 , further comprising a hoist assembly, comprising a hoist winch and a hoisting cable, extending from the hoist winch via sheaves over the tip of the jib to a load suspension device.

19. The marine knuckle boom crane according to claim 1 , further comprising a hoist assembly, comprising a hoist winch and a hoisting cable, extending from the hoist winch via sheaves over the tip of the jib to a load suspension device.

20. A marine knuckle boom crane comprising:
a stationary pedestal to be mounted to or formed integral with a vessel;
a crane housing having an upper portion, a central portion and a lower portion, the crane housing being rotation

Assignees

• Itrec Bv

Inventors

• Roodenburg Joop
• Weterings Hendrikus Jacobus

Classifications

• B66C23/82

  Luffing gear · CPC title

• B66C23/52 Primary

  Floating cranes (floating dredgers E02F) · CPC title

• B63B27/10

  of cranes · CPC title

• B66C23/64

  Jibs · CPC title

• B66C23/66

  Outer or upper end constructions · CPC title