EP1649109B1

EP1649109B1 - Installation for resiliently supporting a spud pole

Info

Publication number: EP1649109B1
Application number: EP04774851A
Authority: EP
Inventors: Arie De Jager
Original assignee: IHC Holland lE BV
Current assignee: IHC Holland lE BV
Priority date: 2003-07-29
Filing date: 2004-07-29
Publication date: 2008-05-28
Anticipated expiration: 2024-07-29
Also published as: WO2005010285A1; NL1024018C2; DE602004014153D1; EP1649109A1

Description

The invention relates to an installation for resiliently supporting that part of a spud pole carriage in which a spud pole can be accommodated, which spud pole carriage can travel along rails on a dredger, according to the preamble of claim 1.
The spud pole carriage must be able to travel over the dredger since after the spud pole has been positioned in the ground it must be possible to move the vessel with respect to the latter. Furthermore, the installation will be so designed that when the spud pole has been put into the ground said spud pole is able to make swinging movements, such as by bending, with respect to the dredger.
In an installation disclosed in NL-A 1011753 use is made of cables for moving the carriage, which cables can also serve for resiliently absorbing loads exerted on the carriage by the spud pole.
One disadvantage with this arrangement is that in the event of the cable breaking the spud pole can fall away. Furthermore, the unit is not easy to maintain and is difficult to inspect and there is risk of corrosion. Furthermore, the flexibility cannot be influenced and the carriage cannot be set in a truly fixed position.
NL-C 135629 discloses an installation according to the preamble of claim 1, comprising a spud pole carriage that is able to tilt with respect to the wheel axles, provided with the wheels that are guided between rails permanently fixed to the vessel. For this purpose the ends of the two axles of the spud pole carriage are accommodated in slots in the side cheeks of the carriage. Each end of an axle is supported in that a compression spring is fitted above and below it.
This is associated with a complex construction since the axles have to be held in place in the axial direction, whilst fitting of the springs will not be easy. Furthermore, the entire carriage can tilt to some extent.
The aim of the invention is, now, to eliminate these drawbacks and to this end the invention makes provision that the part of the spud pole carriage in which a spud pole can be accommodated is supported with respect to the spud pole carriage such that it can swing and is joined to the one end of an arm extending essentially in the horizontal direction in the carriage, the other, free end of which arm is resiliently supported in the vertical direction with respect to the spud pole carriage parts.
The spud pole carriage and the wheels thereof thus always remain in the same position. Since the arm will have a certain length, the forces acting on the free end thereof can be kept relatively low.
According to one embodiment, with this arrangement the free end of the arm can be accommodated in a simple manner between two blocks made of rubber or a similar material, which are supported by the spud pole carriage.
If a "rigid" joint is desired, then in a non-claimed embodiment the blocks can then be replaced by a solid material, such as steel, or other measures can be taken in order to achieve this.
Advantageously, however, provision can also be made that the free end of the arm is supported by at least one hydraulic/pneumatic, double-acting pressure medium cylinder, which at one end is connected to a part of the spud pole carriage and at the other end is connected directly or indirectly to a part that is joined to the arm.
This has the advantage that the flexibility of the system can be set by varying the pressure of the medium or of the media. Furthermore, the fluctuations in the stresses that are exerted by the spud pole can be measured by measuring pressures of the medium or the media. This can offer advantages when using the dredger. Such an installation is also easy to maintain, with all the associated advantages.
The invention will be explained in more detail with reference to illustrative embodiments shown in the drawing, in which:

Fig. 1 shows, diagrammatically, a side view of part of a dredger with a spud pole carriage provided with an installation according to the invention and with a part of the spud pole coupled to the carriage;
Figs. 2 - 5 show, diagrammatically, side views of embodiments of an installation according to the invention; and
Fig. 6 shows a diagram of the way in which a hydraulic/pneumatic double-acting pressure medium cylinder used according to the invention can operate.

Figure 1 shows part of a dredger 1, on which rails 2 have been installed for guiding the wheels 4, mounted on axles 3, of a spud pole carriage 5.
An accommodating part 6 for a spud pole 7 is connected to the spud pole carriage 5, which accommodating part can turn about the shaft 8. The installation 9 by means of which the spud pole 7 can be brought from the position lying on the vessel into a spud pole carriage 5 is also shown diagrammatically in Fig. 1. This installation is known per se, so a further description thereof is considered to be superfluous.
An arm 10 that extends essentially in the horizontal direction in the carriage 5 and is supported at its free end 11 is joined to the accommodating part 6. The mode of support shown in Fig. 1 will be explained in more detail with reference to Fig. 4.
Fig. 2 shows the arm 10 that is joined, such that it can swing, to the accommodating part 6, only the shaft for turning 8 of which is indicated in Fig. 2. The free end 11 of the arm 10 is between two rubber blocks 12, which are supported by the parts 13 and 14 of the spud pole carriage 5. The rubber blocks 12 will thus endeayour to hold the arm 10 in the desired position, the load exerted by the spud pole 7 on the accommodating part 6 being absorbed.
In the embodiment according to Fig. 3, the arm 10 is joined to a part 15 that is coupled to the part 13 of the spud pole carriage 5 by means of two pressure medium cylinders 16 operating hydraulically/pneumatically and fitted on either side of the arm 10, the operation of which cylinders will be explained in more detail with reference to Fig. 6.
Fig. 4 shows the option of supporting the part 15 joined to the arm 10 by means of a yoke 17 that on one side is coupled to the part 13 of the spud pole carriage 5 by means of a rod 18 and on the other side by means of pressure medium cylinders 16 operating hydraulically/pneumatically.
The embodiment according to Fig. 5 to a large extent corresponds to that in Fig. 4. However, the yoke 17 is now directly joined to the arm 10 and the rod 18 has been replaced by a hydraulic/pneumatic pressure medium cylinder 16. The number of cylinders has thus been doubled.
Fig. 6 shows the operation of a hydraulic/pneumatic pressure medium cylinder 16. The piston 19 thereof has been drawn in the mid position. In this position no force is exerted on the arm 10, which is not shown and which is connected indirectly to the piston rod 20.
A non-compressible medium, such as oil, is present in the space above and below the piston 19 and each space is in communication with an accumulator 21 with a piston 22 therein. Pressure is exerted on the other side of the piston 22 by means of air or another gas that is in the accumulators 23 at a certain pressure.
Furthermore, the spaces on either side of the piston 19 are each connected to a buffer accumulator 24, containing the piston 25 therein on which, on the other side, the pressure of a medium such as air or another gas is exerted.
If pressure is now exerted on the piston rod 20 in a specific direction, such as, for example, in the direction of the arrow P, oil will flow towards the lower buffer accumulator 24 and away from the upper buffer accumulator 24. The compressible medium that is above the piston 25 in the lower buffer accumulator 24, which piston 25 is moving inwards as a result, will be put under higher pressure, so that movement of the piston rod 20 is counteracted. When the piston 19 moves downwards, oil from the accumulator 21 will be fed to the space located above the piston, so that a vacuum will not be produced in the space concerned.
The pressure of the medium in each of the buffer accumulators 24 can be measured by the manometer 26, whilst fill lines, shut-off valves and the like, which are not indicated in more detail, will also be provided.
It will be clear that only a few possible embodiments of an installation according to the invention have been shown in the drawings and described above and that many modifications can be made without going beyond the scope of the claims.

Claims

Installation for resiliently supporting that part (6) of the spud pole carriage (5) in which a spud pole (7) can be accommodated, which spud pole carriage can travel along rails (2) on a dredger (1), and is provided with wheels (4) mounted on axles (3) as well as with parts (13, 14, 15, 16, 17, 18, 19, 20) supporting said part (6) in which a spud pole (7) can be accommodated, characterised in that said part (6) of the spud pole carriage (5) in which a spud pole (7) can be accommodated is supported with respect to the spud pole carriage (5) such that it can swing and is joined to the one end of an arm (10) extending essentially in the horizontal direction in the carriage, the other, free end (11) of which arm is resiliently supported in the vertical direction with respect to the spud pole carriage (5) parts (13, 14, 15, 16, 17, 18, 19, 20).
Installation according to Claim 1, characterised in that the free end (11) of the arm (10) is accommodated between two blocks (12) made of rubber or a similar material, which are supported by parts (13, 14) joined to the spud pole carriage (5).
Installation according to Claim 1, characterised in that the free end (11) of the arm (10) is supported by at least one hydraulic/pneumatic, double-acting pressure medium cylinder (16), which at one end is connected to a part (13) of the spud pole carriage and at the other end is connected directly or indirectly to a part (15, 17) that is joined to the arm (10).