Counterweight Backhoe dredger

Abstract

The present invention relates to a vessel comprising an excavator for dredging or shifting soil for cleaning watercourses, the excavator comprising; a weight balanced boom hingeably supported around a boom hinge axis, a bucket-arm hingeably connected to the boom, and provided with a bucket and/or digging tool at a free end of the bucket-arm, wherein a counterweight is connected to the boom and wherein the counterweight is positioned with respect to the boom such that a centre of gravity of the counterweight is above and about vertically aligned with the boom hinge axis when the bucket and/or digging tool is at a lowest digging position.

Claims

1. A vessel comprising an excavator for dredging or shifting soil for cleaning watercourses, the excavator comprising; a weight balanced boom hingeably supported around a boom hinge axis, a bucket-arm hingeably connected to the boom, and provided with a bucket and/or digging tool at a free end of the bucket-arm, wherein a counterweight is connected to the boom and wherein the counterweight is positioned with respect to the boom such that a centre of gravity of the counterweight is above and about vertically aligned with the boom hinge axis when the bucket and/or digging tool is at a lowest digging position.

2. The vessel according to claim 1, wherein the boom extends at both inboard and outboard sides of the boom hinge axis and the counterweight is connected with a boom inboard section.

3. The vessel according to a preceding claim 1, wherein the boom is of one-piece.

4. The vessel according to claim 1, wherein the boom has a longitudinal axis, and the boom hinge axis is offset over a spacing S with respect to the boom longitudinal axis.

5. The vessel according to claim 1, wherein the excavator comprises a transverse member coupled with the boom, wherein the boom is hingeably coupled with a main frame through the transverse member.

6. The vessel according to claim 1, wherein the counterweight is fixedly connected with the boom.

7. The vessel according to claim 2, comprising a hydraulic drive system having a boom cylinder, wherein the boom cylinder is coupled with the boom inboard section to drive the boom.

8. The vessel according to claim 7, wherein the boom cylinder is coupled with the boom proximate a free end of the boom inboard section.

9. The vessel according to claim 7, wherein the boom cylinder is hingeably supported above the boom hinge axis.

10. The vessel according to claim 1, wherein the excavator comprises a turntable for supporting the excavator and to allow the excavator to rotate around a vertical rotating axis, and wherein the centre of gravity of the counterweight is above the turntable when the bucket and/or digging tool is at its lowest digging position.

11. The vessel according to claim 10, wherein the centre of gravity of the counterweight is about vertically aligned with the vertical rotating axis when the bucket and/or digging tool is at its lowest digging position.

12. The vessel according to a claim 1, wherein the vessel comprises equipment coupled with the excavator for driving the excavator, wherein the equipment is at least partly, in particular entirely, arranged below a deck level.

Description

SHORT DESCRIPTION OF DRAWINGS

[0040] The present invention will be discussed in more detail below, with reference to the attached drawings, in which

[0041] FIG. 1 is a perspective view of a vessel according to the invention;

[0042] FIGS. 2 and 3 is a side view of the vessel of FIG. 1 in different positions;

[0043] FIG. 4 is another embodiment of a boom.

DESCRIPTION OF EMBODIMENTS

[0044] FIG. 1 is a perspective view of a vessel 1 according to the invention. FIGS. 2 and 3 is a side view of the vessel 1 of FIG. 1. FIGS. 1 and 3 shows the vessel 1 in a position wherein a centre of gravity 16 of the counterweight 6 is above and about vertically aligned with the boom hinge axis 7 when the bucket 5 is at a lowest digging position. FIG. 2. shows the vessel 1 in a position wherein the counterweight 6 is lowered and the bucket 5 is lifted and ready to swing to above a loading space (not shown). The vessel 1 according to the invention is described referring to FIG. 1-3.

[0045] The vessel 1 comprises an excavator 2. The excavator 2 is suitable for dredging or shifting soil in particular for cleaning watercourses. The excavator is highly integrated with the construction of the vessel 1. This integration allows to mount equipment 20 of the excavator 2 with the vessel as can be best seen in FIG. 3. This way, the equipment is stationary and needs not rotate with the main frame 19 of the excavator 2. The equipment 20 is only schematically shown and may include a main drive system and auxiliary systems. The equipment 20 can be installed within the vessel 1 itself, providing free deck space. Additionally, this will allow to gain vessel stability when performing operations. It will be understood that the equipment 20 can be provided on deck as well as desired.

[0046] The excavator 2 comprises a boom 3 for raising and lowering the bucket 5 and bucket-arm 4. The boom 3 is hingeably supported around a boom 3 hinge axis 7. The boom 3 is hingeably coupled to a main frame 19 of the excavator 2. The boom 3 is weight balanced. Therefore, a counterweight 6 is arranged with the boom 3. The counterweight 6 is fixedly connected with the boom 3.The counterweight 6 is positioned with the boom 3 in such a way that a centre of gravity 16 of the counterweight 6 is above and about vertically aligned with the boom 3 hinge axis 7 when the bucket 5 and/or digging tool is at a lowest digging position as best shown in FIG. 1 and FIG. 3.

[0047] The excavator 2 comprises a bucket-arm 4 for swinging the bucket 5 with respect to the boom 3. Therefore, the bucket-arm 4 is hingeably connected to the boom 3. The free end of the bucket arm 4 is provided with a bucket 5. The bucket 5 is hingeably connected to the bucket-arm 4. The bucket 5 is provided with digging tools 17 to facilitate digging.

[0048] The boom 3 extends at both inboard and outboard sides of the boom hinge axis 7 as best shown in FIG. 2. The boom 3 is of one piece. Here, the boom 3 is made of plate construction work. The bucket-arm 4 is connected with the boom outboard section 21. The counterweight 6 is connected with the boom inboard section 8. The boom 3 has a longitudinal axis 10. The longitudinal axis 10 runs from the counterweight 6 to the hinge joint 18 of the boom 3 and the bucket-arm 4. The boom 3 hinge axis 7 is offset with respect to the boom longitudinal axis 10. The boom 3 hinge axis 7 is offset with respect to the boom longitudinal axis 10 over a spacing S.

[0049] The excavator 2 comprises a transverse member coupled with the boom 3. In this case, the transverse member is integrated with the plate construction work that forms the boom 3. Therefore, the boom 3 has a sort of triangular shape in side view. The boom 3 is hingeably coupled with the main frame 19. The boom 3 is hingeably coupled with the main frame 19 at a location near deck position 22 which improves the stability and operational movement of the embodied excavator. This enables less energy consumption per full turning circle of the excavator, when compared with standard excavators. The boom 3 is hingeably coupled with the main frame through the transverse member.

[0050] The vessel 1 comprises a hydraulic drive system 11. The hydraulic drive system 11 is not described because it is well known how to drive an excavator having a boom 3, bucket-arm 4 and bucket 5 whit the use of an hydraulic system. The hydraulic drive system 11 has a boom cylinder 12. The boom cylinder 12 is coupled with the boom 3 and the main frame 19 to raise and lower the boom 3 while hinging around the boom hinge axis 7. The boom cylinder 12 is coupled with the boom inboard section 8 to drive the boom 3. The boom cylinder 12 is coupled with the boom 3 proximate a free end 13 of the boom inboard section 8. The boom cylinder 12 is hingeably supported above the boom hinge axis 7 as best shown in FIG. 3.

[0051] The excavator comprises a turntable 14. The turntable 14 is configured for supporting the excavator 2 and to allow the excavator 2, or more precisely the main frame 19 of the excavator 2, to rotate with respect to the vessel 1. The turntable 14 allows the main frame 19 to rotate around a vertical rotating axis 15. The centre of gravity 16 of the counterweight 6 is above the turntable 14 when the bucket 5 and/or digging tool is at its lowest digging position as best seen in FIG. 3. In particular, the centre of gravity 16 of the counterweight 6 is about vertically aligned with the vertical rotating axis 15 when the bucket 5 and/or digging tool is at its lowest digging position.

[0052] Where the counterweight 6 is shown as a rectangular body, the skilled person will appreciate that the counterweight 6 can be provided with different shapes and/or configurations. The embodied boom 3 is a one piece. A number of attachment configurations are provided such that the connections between the bucket arm 4 and the boom 3 can be easily and rapidly done. The boom 3 is configured such that the connection of the boom 3 to the vessel 1 via the turning table 14 can be handled with an on-board crane (not shown). Where a turning table 14 is shown as the connection of the boom 3 to the vessel 1, any other suitable connection is conceivable, like a flexible base, which is a known connection and is a base that can adapt to different configurations.

[0053] The skilled person will appreciate that the vessel 1 might comprise at last two spuds (not shown), preferably three, to provide vessel stability as well as safety when performing excavations.

[0054] FIG. 4 shows a side view of another embodiment of the boom 3. Only differences with the boom 3 as shown in FIG. 1-3 are described. The boom 3 is made of beam segments 23, 24. The embodied boom 3 is a one piece comprising beam segments. The transverse beam member 9 is coupled with the longitudinal beam of the boom 3. The beam segments 23, 24 can be extended in length depending on the excavation depth requirements. The transverse beam member 9 is coupled with the longitudinal beam of the boom 3. The transverse beam member 9 comprises the boom hinge axis 7 at its lower portion. As can be clearly seen in this figure, the boom hinge axis 7 is offset over the spacing S with respect to the boom longitudinal axis 10. It should be understood that the height or distance of the spacing S will be determined in relation with the boom length and the mass of the counterweight 6, besides some other parameters e.g. distances between the different points of rotation of the boom 3.

[0055] The present invention has been described above with reference to a number of exemplary embodiments as shown in the drawings. Modifications and alternative implementations of some parts or elements are possible, and are included in the scope of protection as defined in the appended claims.