The present invention concerns a cleaning device of the hull of a ship. The invention refers to the field of maritime navigation of any kind, and in particular to the problems connected with the development of algae or other kinds of covering of the surface of the hull caused by animal or vegetal agents compromising the surface and consequently the streamline of the hull itself, causing an increase of consumption and limiting the maximum speed.

More in particular, the invention refers to the periodic maintenance of the hull of a ship, with the aim of preventing any excessive development of algae or formation of other foreign bodies on its surface.

It is known that ships, in particular when they are at their mooring, regularly need, with a frequency varying according to the local conditions, to be beached, on a suitable slip, in order to allow for the cleaning of the bottom works or hull. Thus, the cleaning operation itself need a preliminary operation of beaching the ship, called haulage, necessarily implying an important consumption of time, during which the ship is out of service, and money.

Alternatively, it is possible to rely upon a scuba operator, who will proceed to the cleaning of the hull by means of manual work, for example by means of brushes and scrapers, without the need for haulage.

Some devices were also realised allowing for the cleaning of the hull of ships preventing haulage. In particular, these devices are provided with brushes or ejectors of compressed water for cleaning the hull, arranged on a platform that can be moved along the hull either manually or by means of suitable moving means. However, the solutions of this kind present the problem of being controlled with difficulties, unless they are controlled from a different ship with respect to the one that has to be cleaned.

In order to solve this problem, patent US4462328 discloses a device constituted by a platform provided with wheels and ejecting nozzles of compressed water facing towards the hull, and a bigger nozzle facing towards an opposite direction ensuring the adhesion of the device to the hull, the movement being entrusted to two ropes, a horizontal rope and a vertical rope, connected at an end with the device and with the opposed end respectively with means for controlling the length of the horizontal rope and with means for controlling the length of the vertical rope, said controlling means being optionally fixed to the hull of the ship or to a wharf.

The international application WO02096748 discloses a cleaning device provided with a surface made of an elastically deformable material standing wear and tear which is slided along the hull of a ship by means of a rope, connected to the device, transversally passing from one side to the other of the hull, passing below the keel of the hull. Due to its features, the device results to be unsuitable for cleaningportions of the hull respectively closer to the stern and to the bow of the ship.

Finally, UK patent application N. GB2444479 discloses a cleaning device for the hull of ships comprising an elix propeller and a brush positioned at an end of a curved pole, provided with a handle for an operator on board of the ship moving it, the propeller having the task of assuring the adhesion amongst the device and the surface of the hull. This kind of solution needs the intervention of an operator, hence it is not completely automated.

In this context is presented the solution according to the present invention, with the aim of providing a cleaning device of the hull of a ship completely automated, conceived for a preventive and frequent cleaning of the hull, in order to prevent, beside the development of colonies of algae, also that of the so called "stellate barnacle" without the need of "beaching" the ship.

These and other results are obtained according to the present invention by proposing a cleaning device of the hull of a ship completely automated, able to run on the whole surface of the hull, by moving supported by two ropes, respectively fixed at the bow and at the stern of the ship.

The purpose of the present invention is therefore that of realising a device allowing for overcoming the limits of the solutions according to the prior art and obtaining the previously described technical results.

A further purpose of the invention is that said device can be realised with substantially limited costs, both the production costs and the management costs. Not last purpose of the invention is that of realising a device that is substantially simple, safe and reliable.

It is therefore a specific object of the present invention a cleaning device of the hull of a ship, of the type comprising a side on which one or more brushes and an elix propeller providing for the necessary thrust for adhering the cleaning device to the surface of the hull, comprising a floodable sink, two motorised winches around which two ropes are wound, respectively fixed at the bow and at the stern of the ship, means for detecting the amount of inclination and means for controlling said winches.

Preferably, according to the invention, said floodable sink can be provided with a flooding valve and an emptying pump.

Further, always according to the invention, said cleaning device can be further provided with a container of the overlength of said ropes.

In particular, according to the present invention, said means for detecting the amount of inclination comprise an inclinometer and said means for controlling said winches comprise a PLC and a radio control.

The effectiveness of the device of the present invention, allowing for performing the cleaning of the hull simply, accurately and not too expensively, is evident; thus making possible to proceed with a frequent and therefore preventive and programmed cleaning of the hull.

Consequently, the cleaning device of the hull of a ship of the present invention allows for reducing the number of calls needed and the consumption of antivegetative paints (constituted by heavy metals and chemical substances that are dangerous for the environment and man).

The present invention will be now described, for illustrative non limitative purposes, according to a preferred embodiment, with particular reference to the figures of the enclosed drawings, wherein: - figure 1 shows a perspective view of a cleaning device of the hull of a ship according to the present invention, from the side facing the hull,

- figure 2 shows a perspective view of the cleaning device of figure 1 , from the side opposed to that of figure 1 , and

- figure 3 shows a schematic view of a ship and the device of figure 1.

Making reference to the figures, the cleaning device of the hull of a ship according to the present invention is referred to as a whole with the numeral 10 and comprises a flat side 11 on which a plurality of brushes 12 is arranged, a floodable sink 13, provided with a flooding valve and a bilge pump for emptying, two motorised winches 14 around which two ropes are wound 15, respectively fixed at the bow and at the stern of a ship 16. The cleaning device 10 is further provided with a container 17 for the overlength of the two ropes 15 and with an elix propeller 18 providing for the necessary thrust for adhering the cleaning device 10 to the surface of the hull to be cleaned.

Lastly, the cleaning device 10 comprises an inclinometer and un control system constituted by a PLC and a radio control.

The functioning of the cleaning device of the hull of a ship according to the present invention provides for an initial step according to which the cleaning device 10 is placed in correspondence of the point of the hull from which it is desired to start cleaning, for example at the stern, operating the winches 14 by means of the radio control, so that the winch positioned at the stern collect the respective rope 15 and the winch positioned at the bow, on the contrary, release it. The two winches 14 are powered by electric gear motors (provided with a worm drive and with encoder) controlled by a PLC, taking care of synchronising the winding/unwinding speed of the winches 14.

During this first step, the cleaning device 10 can float, because the sink 13 is empty. After positioning it so that it adheres to the hull, the cleaning device 10 floods and its weight pushes it downward.

Since it is bound to the ropes 15, operating the winches 14 so that they release the respective ropes 15 with synchronous speed (unwinding) the cleaning device 10 will cover a route downwards with a direction that is perpendicular to the waterline of the ship 16.

The PLC, suitably programmed, controls, operating the elix propeller 18 so that the cleaning device 10 adheres to the hull, the asset variation measured by the inclinometer. Until the inclinometer of the cleaning device 10 does not exceed an asset variation of 90°, the cleaning device 10 continues its descent unwinding the ropes from the winches 14, the elix propeller being idle, proceeding with steps having a set length, after each step operating again the elix propeller 18 and controlling again the asset variation measured by the inclinometer.

The descent of the cleaning device 10 continues until the inclinometer measures an asset variation over 90° with respect to the initial asset. When it happens it is because the cleaning device 10 passed the keel of the hull. After this moment the real cleaning step can start. The PLC, verified this situation, drives the continuous operation of the elix propeller 18, in order to assure the adhesion of the cleaning device 10, in particular of the brushes 12, to the hull. At the same time, the PLC drives the winches 14 so that they wind the ropes 15 synchronously, in order to obtain the going back up of the cleaning device 10.

Thanks to these two simultaneous actions, since the brushes 12 adhere to the hull, and, at the same time, the cleaning device 10 moves along the hull, with an inverted path with respect to that of the first step, the resulting scraping action on the surface of the hull allows for obtaining the cleaning of the interested portion of the hull.

This second step automatically ends when the cleaning device 10 reaches the waterline.

Then, the cleaning device 10 is moved parallel to the waterline to arrive at a position adjacent to that previously occupied. The steps of descent and subsequent cleaning during the going back up are repeated on this new portion of the hull. These operations can then be repeated different times according to the conditions of the hull.

The present invention was described for illustrative non limitative purposes, according to preferred embodiments, but it has to be understood that variations and/or modifications can be made by the skilled in the art without for this reason escaping the respective scope of protection, as defined by the enclosed claims.