Double jib slewing pedestal crane

Patent metadata

Field	Value
Publication number	US-2016332849-A1
Application number	US-201415110488-A
Country	US
Kind code	A1
Filing date	Dec 30, 2014
Priority date	Jan 10, 2014
Publication date	Nov 17, 2016
Grant date	—

Abstract

A double jib slewing pedestal crane includes a main jib and a secondary jib, and a secondary jib positioning device to support and position the secondary jib with respect to the main jib and actuate the pivotal movement of the secondary jib. The secondary jib positioning device includes a secondary jib positioning cable; a spoke structure fixed to the secondary jib and extending radially outward; a tension chain connected at one end to the secondary jib positioning cable and at the other end to the secondary jib and/or to the spoke structure, wherein the spoke structure is adapted to support the tension chain.

First claim

1 . A double jib slewing pedestal crane comprising:
a stationary pedestal; a crane housing mounted to the pedestal and adapted to slew relative to the pedestal about a vertical slew axis; a main jib comprising an inner end connected pivotably about a first horizontal pivot axis to the crane housing, allowing an up-and-down luffing movement of the main jib, and opposed thereof two forked outer ends between which a jib axle extends defining a second horizontal pivot axis; a luffing assembly comprising a luffing winch and a luffing cable extending between the main jib and the crane housing; a secondary jib comprising a forked inner end defining a left-hand fork end and a right-hand fork end, the left-hand fork end and the right-hand fork end being connected pivotably to the jib axle, allowing a pivotal movement of the secondary jib with respect to the main jib; an object suspension device to which an object is connectable; a hoist assembly comprising a hoist winch and an associated hoisting cable, the hoisting cable extending from the winch to the object suspension device, such that upon actuation of the winch, the object suspension device can be raised and lowered; wherein the forked inner end of the secondary jib allows to receive the hoisting cable between the left-hand and right-hand fork ends on the jib axle; and a secondary jib positioning device arranged between the secondary jib and the crane housing, adapted to support and position the secondary jib with respect to the main jib and actuate the pivotal movement of the secondary jib; the secondary jib positioning device comprising:
a secondary jib positioning winch cooperating with a secondary jib positioning cable, the secondary jib positioning cable extending between the crane housing and a tension chain;
a spoke structure fixed to the secondary jib and extending radially outward from the jib axle, comprising one or more right-hand spokes attached to the right-hand fork end of the secondary jib and one or more left-hand spokes attached to the left-hand fork end of the secondary jib, wherein between the right-hand spokes and the left-hand spokes, a space is defined through which the hoisting cable extends, wherein the length of the forked outer ends of the main jib is such that the gap between the forked outer ends of the main jib allows to pass at least a portion of the spoke structure; and
a tension chain connected at one end to the secondary jib positioning cable and at the other end to the secondary jib and/or to the spoke structure, the spoke structure being adapted to support the tension chain.

2 . The double jib slewing pedestal crane according to claim 1 , wherein the spoke structure comprises a first spoke fixed essentially perpendicular to the secondary jib.

3 . The double jib slewing pedestal crane according to claim 2 , wherein the tension chain is connected at one end to the secondary jib positioning cable and at the other end to the first spoke.

4 . The double jib slewing pedestal crane according to claim 2 , wherein the tension chain is connected at one end to the secondary jib positioning cable and at the other end to the outer end of the secondary jib.

5 . The double jib slewing pedestal crane according to claim 1 , wherein parallel right-hand and left-hand second spokes are provided, including a second angle with respect to the secondary jib, and parallel right-hand and left-hand third spokes are provided, including a third angle with respect to the secondary jib, wherein the second and third right-hand spokes are interconnected at intermediate portions of the spokes via a strut, and wherein the second and third left-hand spokes are interconnected at intermediate portions of the spokes via a strut.

6 . The double jib slewing pedestal crane according to claim 1 , the tension chain comprising a series of interconnected links, and the radial outer end of the spokes being adapted to support a link of the tension chain.

7 . The double jib slewing pedestal crane according to claim 6 , wherein the tension chain comprises rods, mutually connected via a pivot, the radial outer end of the spokes being provided with seats for receiving the pivot.

8 . A double jib slewing pedestal crane comprising:
a stationary pedestal; a crane housing that is mounted to the pedestal and adapted to slew relative to the pedestal about a vertical slew axis; a main jib comprising an outer end and an opposed inner end which is connected pivotably about a first horizontal pivot axis to the crane housing, allowing an up-and-down luffing movement of the main jib; a luffing assembly comprising a luffing winch and a luffing cable extending between the main jib and the crane housing; and a secondary jib comprising an outer end and an opposed inner end connected pivotably about a second horizontal pivot axis to the outer end of the main jib, allowing a pivotal movement of the secondary jib with respect to the main jib; an object suspension device to which an object is connectable; a hoist assembly comprising a hoist winch and an associated hoisting cable; wherein the secondary jib is provided with a hoist cable departing sheave at the outer end and a first mounting facility for a hoist cable retention device close to the inner end and a second mounting facility for a hoist cable retention device between the inner and the outer end, allowing the hoisting cable to extend from the hoist winch, via the departing sheave and via the object suspension device to a hoist cable retention device, such that the hoisting cable comprises one or more first suspension cable parts extending between the object suspension device and the departing sheave, and one or more second suspension cable parts extending between the object suspension cable device and the hoist cable retention device, such that the first and second suspension cable parts extend at a relatively large angle with respect to each other when the hoist cable retention device is mounted at the first mounting facility, and at a relatively small angle with respect to each other when the hoist cable retention device is mounted at the second mounting facility.

9 . The double jib slewing pedestal crane according to claim 8 , wherein the hoist cable retention device is provided on a trolley and the secondary jib is provided with a rail for the trolley, extending between the first and second mounting facility, allowing the hoist cable retention device to move along the secondary jib, thereby changing the angle between the first and second suspension cable parts.

10 . The double jib slewing pedestal crane according to claim 8 , wherein the hoisting cable has a dead end connected to the hoist cable retention device.

11 . The double jib slewing pedestal crane according to claim 8 , wherein the hoist cable retention device is embodied as a guide sheave.

12 . The double jib slewing pedestal crane according to claim 1 , wherein the stationary pedestal is adapted to be mounted to a vessel.

13 . The double jib slewing pedestal crane according to claim 1 , wherein the spoke structure comprises a first spoke fixed to the secondary jib at a first angle of 70-110°.

14 . The double jib slewing pedestal crane according to claim 3 , wherein a tension link is provided between the radial outer end of the first spoke and the outer end of the secondary jib.

15 . The double jib slewing pedestal crane according to claim 8 , wherein the stationary pedestal is adapted to be mounted to a vessel.

16 . The double jib slewing pedestal crane according to claim 2 , wherein parallel right-hand and left-hand second spokes ar

Assignees

• Itrec Bv

Inventors

• Roodenburg Joop
• Weterings Hendrikus Jacobus

Classifications

• B66C23/52 Primary

  Floating cranes (floating dredgers E02F) · CPC title

• B66C23/82

  Luffing gear · CPC title

• B66C23/64

  Jibs · CPC title

• B66C2700/03

  Cranes with arms or jibs; Multiple cranes · CPC title

• B66C23/66

  Outer or upper end constructions · CPC title