EP1273360A2

EP1273360A2 - Apparatus for removing marine organisms and the like

Info

Publication number: EP1273360A2
Application number: EP01128752A
Authority: EP
Inventors: Isao Miyoshi
Original assignee: Individual
Current assignee: Individual
Priority date: 2001-07-06
Filing date: 2001-12-03
Publication date: 2003-01-08
Also published as: EP1273360A3; JP2003019998A; US20030005874A1

Abstract

To provide a simple apparatus for removing deposits such as marine organisms from a wall of an underwater structure by applying a natural force such as wave force and tidal force and not by chemicals and the like, in which the apparatus includes many floating bodies (1) prepared by linking the apparatus to perform an operation for removing deposits, and deforms with floating and repeats collision with the wall of the underwater structure to allow effective removal of deposits such as marine organisms. The apparatus for removing marine organisms and the like by floating and colliding the removing apparatus around and with, respectively, a surface of or a position about an underwater or undersea structure, in which the apparatus includes a plurality of elongated spherical hollow bodies or solid bodies (1) to link each other and a protection cover (5) to cover an outer circumference of the hollow body or the solid body, wherein the protection cover is made of a resin having a durometer hardness ranging from 75 to 85.

Description

THE PRESENT INVENTION relates to an apparatus for removing marine organisms and the like (e.g. shells such as oyster, barnacle, mussel and the like, and seaweeds) attached to an underwater structure (for example, a steel pipe pile, H-shaped pile, angular pile, concrete pile and wall, perpendicular pile, horizontal rod, diagonal member, leg, leg of pier, bank, floating quay, float bridge, and pontoon) supporting an offshore structure, such as a sea berth, an artificial island, a pier, a hull such as side or bottom of a ship (particularly, an anchored exhibition ship), an oil fence or shield fence and the like and deposits such as sludge, entangled therewith or attached thereto, by applying a natural force such as wave force, wind force, or tidal force.
Conventionally, maintenance of an underwater structure, such as a pile supporting an offshore structure or the bottom of a ship, is mainly carried out by removing deposits (shells, seaweeds, rust, and sludge) attached to a surface of the underwater structure or the bottom of the ship.
These deposits enhance the corrosion of a steel pipe and the resistance to wave and wind is increased by an aperture of the steel pipe being made irregular by marine organisms firmly attached thereto. Thus, for example, in case of the use of such a structure in a bridge pier, the occurrence of an abnormal vibration can cause a crack or a break in the structure.
In concrete structures, the following phenomenon is observed: the sulfur content of the concrete is removed by marine organisms and hence, although the concrete structure visually appears tough, it is gradually eroded from the surface.
It is necessary, therefore, to periodically remove these deposits and, at present, this removal operation is mainly carried out by manpower using a chaplet rod or a wire brush.
However, many offshore structures have hundreds to thousands of installations; and the cleaning thereof is carried out in or on the sea or water subject to meteorological conditions, such as wave and wind or tidal wave and current, which can cause many dangerous situations and require many workers including, when necessary, divers. The removal of deposits is therefore a long term operation which increases the costs, the period of working, and involves an unsafe working environment.
These situations are also encountered when removing deposits attached to the hull and the bottom of a ship, which, in particular, cause a distinct reduction in the speed of the ship. Therefore, at present, periodical repair and maintenance operations are carried out, in which, for example, deposits are scraped off in a dock.
Many attempts have been made to replace the manual operations described above. For example, a paint containing an anti-fouling agent or a substance to produce toxic ions, which prevents attachment of deposits (shells and seaweeds), is applied to suppress the attachment of marine organisms or to extinguish marine organisms and a pile cover is attached to protect the above described underwater structure. Chemicals, such as anti-fouling agents, however pollute not only the worker but also the nearby area of the sea, thereby causing an environmental pollution problem. Moreover, in practice, it is not possible to prevent marine organisms from attaching to the treated surface entirely and, needless to say, manual removing operations are inevitably carried out periodically.
The present invention aims to provide a solution to the above described problem and provides an apparatus for removing deposits, such as marine organisms and the like, from a structure immersed in water adapted to make the removing apparatus contact the surface of the underwater (hereafter, including the sea and brackish water) structures movable not only vertically but also in various directions by the wind force or wave force (including tidal current and wave), effectively removing deposits attached to concrete or a steel pipe pile or the ship bottom by this motion (repeated collision), and in addition, make it possible to install a structural body, which is used for removal of those deposits, to fit to the external shape of concrete and the steel pipe pile.
The term "marine organisms and the like" includes not only organisms such as shells, seaweeds, planktons, and the like but also organic and inorganic matters such as sludge, sand, gravel, rust, and other materials entangled therewith or attached thereto. In addition, the term "marine organisms and the like" includes aquatic organisms or brackish water organisms. The same problem takes place in environments, where aquatic organisms or brackish water organisms may attach, such as rivers, lakes, and also brackish waters in which fresh water is blended with seawater. The apparatus according to the present invention described in detail later can be applied to all these marine organisms. Consequently, the present invention includes the removal of all of these marine organisms.
The present inventor previously proposed a float type apparatus for removing deposits using the vertically moving wave force, the tidal force and the like (Japanese Patent Application No. 9-164374). By this means, an excellent removal of deposits was achieved, such that such marine organisms, such as shells and seaweeds, attached to concrete and steel pipe piles are substantially removed within a few days.
In addition, by further improvement of such float type apparatus for removing deposits, the present inventor devised an apparatus which relatively slowly and steadily effects the removal of deposits to prolong the life of the structural body, the deposits being steadily and completely removed without any deposits left on the entire surface of an area to which marine organisms attached (Japanese Patent Application No. 9-363304 and Japanese Patent Application No. 10-188068).
As a rule, marine organisms, such as shells and seaweeds, often attach to a place near a water surface (just above or just below the surface) and gradually thicken as they become entangled with dust and mud floating on the water/sea surface. The above described inventions previously proposed are very effective for such removal of deposits.
The present invention is proposed in order to further improve the above described inventions. Marine organisms, such as shells and seaweeds, attach and live occasionally in a range from the surface water to ten or several meters beneath the water surface. In order to remove these organisms, it was proposed in the above patent applications, in one case, to arrange the apparatus for removing deposits as a multi-step system and, in another case, to position an apparatus under the float type apparatus for removing deposits, the apparatus being installed to collect marine organisms and reliquiae that have been removed.
In the above described patent applications, the removing apparatus is in the form of a cylindrical or square protection tube ring fitted to cover an outer circumferential face of a hollow body to prolong the life of the hollow body and, also, the outer circumferential face of the hollow body is made in a special or peculiar shape to make a compatible structure for allowing separate uses for rapid removal and slow removal.
The present invention aims to provide an apparatus which is capable of effectively and completely removing deposits such as marine organisms by employing a simple structure. In addition, the invention aims to provide an apparatus for removing marine organisms and the like attached to the underwater structure and the like which reduces the frequency of replacement and removal of the apparatus, resulting in a safe operation.
Accordingly, the present invention provides an apparatus for removing marine organisms and the like by positioning the removing apparatus in the proximity of a surface of an immersed structure, so that the removing apparatus collides with the said surface of the structure, which apparatus comprises a plurality of bodies linked to each other and a protective cover to cover an outer circumference of each body, wherein the protective cover is made of a resin having a durometer hardness ranging from 75 to 85.
Preferably, at least a part of a circumferential face of the protective cover comprises a plurality of bridge-like projections for colliding against a surface of the immersed structure.
Conveniently, the inner diameter of the protective cover is greater than the outer diameter of the body and the protective cover is held rotatably on the outer circumference of the body.
In a preferred embodiment, the bridge-like projections are parallel to an axis of rotation of the protective cover.
Desirably, the protective cover comprises two separate cup-shaped portions respectively provided with a snap-fit projection and a recess arrangement for securing the cup-shaped portions together.
Preferably, some or all of the bridge-like projections are aligned with respective projections of the snap-fit arrangement.
In a preferred embodiment, the outer circumference of said protective cover is provided with a sleeve.
Conveniently, the sleeve comprises an inner face to fit some or all of a plurality of projections installed on the outer circumferential surface of said protective cover.
Desirably, a plurality of projections are provided on the outer circumferential surface of said sleeve.
Preferably, the sleeve is made of the resin having a durometer hardness ranging from 75 to 85.
In a preferred embodiment of the apparatus, a linking part of the removing apparatus has a freely rotating collar.
Preferably, the collar has an ellipsoid section and is tilted toward the elongated circular in the width direction thereof.
The removing apparatus may comprise ears at two opposite locations of each body for linking said bodies together, the ears at opposite locations of a body being positioned in perpendicular planes.
A first layer of the removing apparatus, that floats on the surface of water or sea, may be linked to a second layer of the removing apparatus, that is suspended from the first removing apparatus, through a linking device such as a chain, and said linking device is covered with a pipe to limit the motion of the linking device.
The removing apparatus may be provided with an openable and closable hole communicating with an internal part of the body.
In adjacent bodies, the ears may be linked to each other by mechanical means such as a bolt and a nut and between these ears, a disk stopper plate, the radius of which is almost the length from the part of bodies, where the ear is attached, to the part where both the above described ears are coupled, may be installed.
In a preferred embodiment, the body is annularly arranged around the immersed structure.
The annularly arranged plurality of bodies, which are floated on the water surface or the sea surface and linked to each other, may be linked to a plurality of removing apparatus, which are suspended from the plurality of bodies with a linking device such as a chain.
Desirably, a buoy is linked to the above described linking device for a plurality of bodies linked to each other.
Preferably, a net is suspended at the bottom of a plurality of the bodies, which are floated on the water surface or the sea surface and linked to each other, and/or the removing device, which is linked in a chain form, by the linking device such as the chain to collect marine organisms and the like; and a plurality of bodies, which are floated on the water surface or the sea surface around the bottom of the hull and linked to each other, and one or a plurality of removing tools, which are linked to any one of both boards of the hull, passed through the bottom to link to the other body, linked in a chain form.
In order that the invention may be more readily understood, embodiments thereof will now be described, by way of example, with reference to the accompanying drawings, in which:
FIG. 1 is a side view of a body employed in an apparatus for removing marine organisms and the like embodying the present invention;
FIG. 2 is a perspective view, illustrating the assembling of a hollow body or solid body having a protective cover;
FIG. 3 is a perspective view, showing in outline the appearance of a two-layer apparatus, formed by linking the hollow bodies or solid bodies, for removing marine organisms arranged around an offshore structure;
FIG. 4 is a perspective view, illustrating the assembling of a hollow body or solid body of the removing apparatus located in a lower layer;
FIG. 5 is a conceptual drawing of an example of the removal of marine organisms deposited on the bottom of the ship by an apparatus embodying the present invention, FIG. 5A being a bird's-eye view and FIG. 5B a transverse sectional view of the ship;
FIG. 6 shows a protective cover having a sleeve on the outer circumference thereof, FIG. 6A being a side view and FIG. 6B being a sectional view thereof, respectively;
FIG. 7 is shows an example of a solid body the outer circumference of which is covered with the protective cover and installation of a socket ring in the outside thereof, FIG. 7A being a partly sectioned front view thereof and FIG. 7B being a transverse sectional view, respectively;
FIG. 8 is a perspective view, showing a freely rotatable collar with a circular or ellipsoid section installed on a connecting part of the removing apparatus; and
FIG. 9 is a perspective view of a two-layer annular removing apparatus, in which a suspending device, such as a chain and the like, is covered with a resin-made pipe.
An embodiment of the present invention is described below with reference to the drawings. FIG. 1 is a side view of an individual removal device of an apparatus for removing marine organisms and the like, the apparatus including a plurality of such removal devices, each in the form of a hollow body 1. The shape of the hollow body 1 is, as shown in the figure, elongated spherical (pepo-shaped or pillow-shaped). The individual hollow bodies are symmetrical excluding the linking part mentioned later.
The inside of the hollow body 1 forms a hollow part 2 (the part circled with a dotted line in FIG. 1). The hollow body 1 is preferably prepared by blow-moulding but may be prepared by other methods.
The removing apparatus removes marine organisms attached to an offshore structure and the like by contact therewith while floating on the sea surface or under the sea and, therefore, it is preferable that the removing apparatus itself is buoyant.
Thus, it is preferable to form the removal devices of the removing apparatus as hollow bodies; however, they could be formed as solid bodies. In the case of a deficit of buoyancy, the floating force of a solid body could be improved by using a buoy. The following description will be presented by using the hollow body as a representative example.
Both ends of the hollow body 1 have ears 3 and 4 (for reference, the "ear" used in the present specification means an ear-like projection and does not mean a biological ear contributing to an auditory sense) for linking the individual hollow bodies. The ears 3 and 4 are formed with respective holes 3 - 1 and 4 - 1, and a fixing element, such as bolt, is inserted through these holes 3 -1 and 4 -1 to link adjacent hollow bodies 1 each other.
As the method for fixing the adjacent hollow bodies 1, loose tightening allows rotatation of the bodies 1 with respect to each other but, if desired, a specific angle between them can be maintained by securely tightening.
As shown in FIG. 1, the ears 3 and 4 extend in respective planes which are orthogonal to one another. Such an arrangement enables the adjacent hollow bodies 1 to move rotatably (rotate) with respect to each other; however, rotational motion in the same direction by the next hollow body 1 (alternately) is inhibited (due to the perpendicular direction) . By this, the following effect is yielded: when the hollow bodies 1 are linked in a ring to form the removing apparatus, the shape of the ring is maintained without any substantial deformation.
In contrast, if the ears 3 and 4 are located in the same plane, rotatable motion is operated in one direction and hence, deviation in a specific direction is caused by influence of the wave force and the like acting on the ring of bodies. However, the ring of linked hollow bodies 1 is bent irregularly and thus, there is no problem as long as a long term removing operation is conducted until removal is completed. Therefore, the present invention includes, as described above, the case where the ears 3 and 4 are located on the same plane.
It is necessary that an overlapped plane of the ears 3 and 4 of the adjacent hollow bodies 1 is accurately located on a center line and therefore, the ears 3 and 4 of all the adjacent hollow bodies 1 are, in consideration of the thickness thereof, installed in a position where one face is positioned on the center line.
The main role of the hollow or solid body is to operate to remove marine organisms and the like by floating on the sea surface and the like. Particularly in the case of a hollow body 1, it is possible to provide an openable and closable hole (not illustrated) to introduce water into the hollow part 2, so that the hollow bodies 1 sink in the sea or water where they float and serve to remove underwater marine organisms and the like attached to the underwater structure.
In case of use for removing operation underwater only, the hole can be kept open from the beginning. The above described "openable and closable hole" is intended to include this possibility.
Using a hard material as the material of the hollow or solid body enables the hollow body or the solid body itself to perform the function of removing marine organisms and the like. However, in order to prevent wearing of the hollow body or the solid body, a protective cover, to be described later, is used.
As the material of the hollow body or the solid body, a resin such as polypropylene, polyethylene, nylon, duracon, hard rubber are preferably used, although materials other than these resins may be usable. However, the required characteristics restrict suitable materials to those having a good mouldability, a role as a floating body, wear resistance, a performance to remove deposits such as shells and seaweeds, and prevention of wearing of the underwater structure such as the steel pipe, concrete, and the like.
FIG. 2 and FIG. 3 show a protective cover 5 fitted to the outer circumferential face of the hollow body or the solid body 1 (hereafter, the same reference numeral 1 is used for the hollow or solid body) with some clearance.
This protective cover 5 is a main feature of the present invention. An inner diameter of the protective cover 5 is somewhat larger than an outer diameter of the body 1, so that the cover 5 is held rotatably on the outer circumference of the body 1.
This protective cover 5 comprises two cup-shaped protective cover parts 5-1 and 5-2, which can be separated and have projections 6 and recesses 7 snap-fitted together. A hole 8 formed at the end of the protective cover 5 is capable of passing both the ears 3 and 4 of the above described body 1.
Hollow parts of two cup-shaped protective cover parts 5-1 and 5-2 are positioned oppositely and coupled together by being passed over the respective ears 3 and 4 of the body 1 and then snap-fitting the projections 6 and recesses 7 together.
The protective cover 5 thereby covers almost the whole of the body 1 and the assembly of an individual removal device is completed. As is evident from the drawings, the assembled protective cover 5 is rotatable on the body 1 but cannot move longitudinally.
The repeated direct collision of the protective cover with the surface of the immersed structure serves to effect the removal of marine organisms and the like from the surface.
The same material as that of the body 1 can be used for the protective cover 5, for example resins such as vinyl chloride, polypropylene, polyethylene, nylon, duracon, and hard rubber. However, materials other than these resins may be usable.
After the above described two cup-shaped protective covers 5-1 and 5-2 are snap-fitted to each other, these covers may be welded to provide firm linkage. Particularly in an open ocean, where the waves are wild, simple snap-fitting may permit the cover parts to separate from each other and, therefore, in such a case, welding is desirable.
After the protective cover 5 is attached to the body 1, as shown in FIG. 2, a connecting bolt 9 is used to connect adjacent bodies 1 to each other. Reference numeral 9-1 represents a nut and the reference numeral 9-2 represents a washer. A series of the bodies 1 linked in a chain is extended to the sea surface around the offshore structure and the like, and both ends of the chain of bodies 1 are finally linked in a ring to complete the apparatus for removing marine organisms and the like.
Thereafter, the apparatus freely executes vertical and other motions under the action of wave power and collides with the underwater structure to effectively remove marine organisms and the like.
A plurality of bridge-like projections 10 are provided on at least a part of the circumferential face of the protective cover 5, so as to collide with the surface of the underwater or undersea structure. These bridge-like projections 10 are preferably on a plane perpendicular to the direction of rotation of the protective cover 5.
In addition, if some or all of these bridge-like projections 10 and the snap-fitted projections 6 and recesses 7 are positioned on the same line, a protective cover having a rational structure and high strength can be formed.
These bridge-like projections 10, in accordance with the vertical movement of the removing apparatus floating on the sea surface by the wave force and the like, collide with the surface of marine organisms or the immersed structure and also rotate irregularly around the circumference of the body 1 to carry out effective removing of marine organisms.
In the early stages of removing marine organisms, the organisms are firmly attached to the surface of the immersed structure and are very difficult to remove by hand and thus the role of the projections 10 is important for removal of marine organisms.
Needless to say, the bridge-like projections 10 of the protective cover 5 suffer the most serious wear; however, even if the bridge-like projections 10 disappear through wear, the removal of marine organisms and the like is maintained by the protective cover 5 alone.
In addition, even if the protective cover 5 itself is worn away and disappears, the body 1 itself has the ability to remove marine organisms and the like and can effectively remove marine organisms and the like. Although it is efficient to replace the cover with a new protective cover 5 at the point where the protective cover 5 has worn, as a rule, at the time of replacement, removal of marine organisms has already almost been achieved.
In the case where the protective cover is hard, a crack occurs occasionally in use and, the harder the resin is, the more rapidly the life thereof shortens . A higher frequency of replacement results in decrease in efficiency of removal of marine organisms and the like. Therefore, prolonging the life of the protective cover 5 is very important.
Consequently, particularly when using for a long time or prolonging the life, it has been found that a soft protective cover is more effective than a hard protective cover. Particularly, it is preferable to prepare it from the resin of the durometer hardness 75 to 85 as shown in JIS K7366. As such material, soft vinyl chloride and the like are preferable.
On the other hand, as shown in FIGS. 6A and 6B, installing a sleeve 30 on the outer circumference of the protective cover 5 allows the life of the protective cover 5 to be further prolonged and provides efficient removal of marine organisms and the like.
If the sleeve 30 is provided with an inner face which fits to a part or all of the bridge-like projections 6 on the outer circumferential surface of the protective cover 5, the sleeve 30 is easily attached and can be stably installed. In addition, when required, the protective cover 5 and the sleeve 30 can be fixed together using an adhesive (resin-based and the like), thereby realising a firmer connection.
FIGS. 7A and 7B, respectively a sectional side view and a transverse view, show a body 1 having protective cover 5 attached to the outer circumference thereof and a sleeve 30 installed on the protective cover 5.
The outer circumference of the sleeve 30 has a plurality of projections 31 extending in the direction perpendicular to the direction of rotation of the protective cover 5, which projections further improve the removal of marine organisms and the like. It is also preferable that the material of the sleeve 30 is, similarly, made of resin having durometer hardness ranging from 75 to 85. By this, wear of the sleeve 30 can be reduced and its life prolonged.
The body 1, the protective cover 5, and the sleeve 30 can all be made from resin and the weight of these three components as a set can be defined as 1.5 kg or less, particularly 1.2 kg or less in total. In other words, the weight of 10 components connected can be defined as 15 kg or less (excluding the weight of the connecting device) and 20 components connected can be defined as 30 kg or less.
Reduction in weight makes transportation, assembly, and installation very easy on land, ship and the sea and also increases the possibilities of motion due to wave, tide and wind and, hence, the removal of marine organisms and the like is further improved. Consequently, a removing apparatus embodying the present invention provides a prominent effect of removing marine organisms and the like and realizes reduction in weight.
It is preferable to provide a freely rotatable collar 32, as shown in FIG. 8 OR FIG. 9, on the linking part of the removing apparatus, the collar having a specific width and a circular or ellipsoid section.
Marine organisms do not attach to the removing apparatus at the places where it continuously collides and contacts with the underwater structure of the offshore structure; however, many marine organisms occasionally and densely attach to the linking part of the removing apparatus at a little distance from the colliding and contacting part. If this happens, the irregular motion of the removing apparatus due the force of the waves and tide disappears, resulting in rapid decrease in the removing effect. The installation of a collar 32 on the linking part of the removing apparatus inhibits attachment of marine organisms by the free motion thereof, thereby smoothing the irregular motion of the removing apparatus. The collar 32 can be installed around a resin-made pipe 33 described later. Similarly, attaching of marine organisms to the pipe is effectively prevented.
In particular, it is preferable for a collar 32 having an ellipsoid section to be tilted toward the elongated circular in the width direction thereof. Such collar 32 is tapered in the direction of the ellipse and thus, contact of the tip thereof with the linking device effectively inhibits attachment of marine organisms.
FIG. 3 shows a structure in which plural sets of bodies 1 are linked together in a plurality of rings to form a top removing apparatus 11 and a bottom removing apparatus 12 arranged one above the other. For convenience of explanation, FIG. 3 shows an example having two rings of bodies 1; however a structure having a single ring on the sea surface only and multistep structures are also possible.
In FIG. 3, the surface of the sea has not been shown and the position of the top removing apparatus 11 corresponds to the position of the sea surface. The bottom removing apparatus 12 is therefore positioned under the sea surface.
The structure of the bodies 1 in FIG. 3 has not been illustrated in detail but includes a protective cover as illustrated in FIG.2. Reference numeral 13 represents a steel pipe pile. In FIG. 3, the diameter of the steel pipe pile 13 is reduced to enable the rings 11 and 12 of bodies 1 to be easily seen. Excessively small diameters of rings 11 and 12 causes an increase in the friction of the bodies 1 against the matter to be removed, the motion of the bodies 1 required for repeated collisions becomes worse, and the efficiency of removal drops. On the other hand, excessively large diameters of rings 11 and 12 of the bodies 1 results in a small contact ratio of the bodies 1 to the matter to be removed small and, hence, the removing efficiency drops . Therefore, diameters of rings 11 and 12 must be adjusted properly in accordance with the thickness of deposits, the diameter of the steel pipe pile 13, the height of the waves, and the like.
As shown in FIG. 3, the bottom ring 12 of bodies 1 under the sea surface is suspended from the top ring 11 by means of suspension devices 14, such as a chain or wire. If hollow bodies 1 are used in the ring 12, the gas (air) within the hollow bodies 1 can be replaced with water and, if solid bodies 1 are used in ring 12, a selected material can be used for the bodies so as to limit buoyancy to a certain degree. The above described structure of the hollow body can be used both to increase buoyancy and to limit buoyancy through sinking by the introduction of water; this multipurpose usability realizes very effective use.
The ring 11 is loaded with the weight of the ring 12 and the chain, wire, and the like suspended to hold it, so that buoys 15 may be provided, if appropriate. The preferred buoy 15 is made of a foamed plastic, is hollow, and prepared by extrusion moulding; however, buoys prepared from other materials and by other methods can also be used.
FIG. 4 shows the structure of the bodies 1 used in the ring 12. The structure of the bodies 1 is same as that used in the ring 11 except that a connecting bolt 18 links a suspension chain 16 and suspension plate 17 with the ring 12 at an appropriate position.
As described above, by installing a two-layer removing apparatus, marine organisms in an area of a wide range on and under the sea surface can be removed.
A net (not illustrated) for collecting marine organisms and the like removed from the underwater structure may be attached to the bottom of the rings 11 and 12.
As described above, in the case where a two-layer or multi-layer removing apparatus is installed, a first layer of the removing apparatus floating on the sea surface moves vigorously under the influence of wave and wind. Thus, it is preferable that the removing apparatus of a second layer thereunder moves according to such motion of the first step of the removing apparatus. However, in the case described above, where the second layer of the removing apparatus is suspended by a chain suspending device 14, the chain suspending device 14 cancels the motion of the first layer of the removing apparatus to cause ineffective motion of the second and following layers.
According to the present invention, in order to solve this problem, as shown in FIG. 9, the suspending device 14 such as the chain and the like as described above is covered with a resin-made pipe 33 to stop the motion of the suspending device 14. By this, a lower layer (the second and following layers) of the removing apparatus can move almost in accordance with the motion of the first layer of the removing apparatus and hence, the effectiveness of a two-layer or multi-layer removing apparatus can be further increased.
The collar 32 described above can be arranged around the resin-made pipe 33 to effectively prevent deposition of marine organisms thereon.
FIG. 5 shows an example of effective removal of marine organisms such as shells and seaweeds deposited firmly on the bottom of a ship within a short period. FIG. 5A is a drawing illustrating the concept of the present apparatus in a bird's-eye view and FIG. 5B is a sectional view. Reference character WL represents a water surface.
Bodies 1 are linked together to form one or more removing apparatus 21 which are floated in the sea around the bottom of the hull 20 of the ship. A protective cover 5, similar to that described above, is attached to the outer circumferential face of body 1. A single-dotted chain line indicates the arrangement of the bodies 1 and the removing apparatus 21, which are linked like a chain.
Similarly to the removing apparatus shown in FIG. 3 or FIG. 4, the removing apparatus 21 shown in FIG. 5 can employ bodies 1 having a structure, in which air in the body 1 can be replaced by water.
A buoy 19 can be installed at appropriate places in the linked bodies 1 to improve buoyancy. A rope 22 is attached to the bow and stern of the ship to enable adjustment of the length thereof to adjust the positioning of the linked bodies 1.
In such an apparatus embodying the present invention, the waves and wind beating against the hull 20 cause irregular deformation of the body 1, to which the protective cover 5 is attached, and collision thereof with the bottom of the ship. In addition, in accordance with this, one or a plurality of the removing apparatus 21, which are passed around the bottom of the ship and are linked like a chain, can repeat irregular motion and collision with the bottom of the ship to effectively remove marine organisms and the like deposited on the bottom of the ship.
Each body 1 with its protective cover 5 is linked to adjacent bodies 1 and, therefore, the linked hollow bodies or solid bodies 1 can be deformed only to a limited degree around the underwater structure.
The limitation of deformation is due to an alternate change in the direction of the linking of the linked bodies 1 (direction of the linking ears). Therefore, the linked bodies 1 do not deform unlimitedly, but if they are annularly linked, for example, as a whole, they keep the shape thereof to a certain degree when deformed. Consequently, ineffective motion of the linked hollow bodies or solid bodies 1 does not take place and the removing effect is increased.
Apparatus embodying the present invention removes marine organisms and the like by mechanically applying natural forces, such as wind, wave and tide, and not by chemicals and the like and has excellent effects in that: the linked bodies, which are linked by a linking mechanism and capable of rotating in a specific range, are arranged to improve buoyancy and also to avoid ineffective motion; the protective cover arranged on the outer circumferential face of the body prolongs the life of the apparatus, contacting and colliding with the immersed structure or the bottom of the ship and reducing the frequency of replacement and removal of the apparatus to provide stable operation for removing deposits; and effective removal of marine organisms, such as shells and seaweeds firmly attached not only to an immersed structure, such as a vertical pile, but also to a structure extending horizontally or diagonally or the bottom of a ship can be carried out within a short period.
The two-part protective covers 5 are easy to attach to the bodies 1. In addition, the bridge-like projections on the protective cover impact against marine organisms and the like and further enhance the removing effect.
In addition, the following excellent effects are achieved: the apparatus for removing deposits such as marine organisms and the like is installed by sinking in water, collides repeatedly with deposits existing around the water surface and under the water surface simultaneously to remove them, and is capable of effectively removing such marine organisms as shells and seaweeds firmly attached to almost all areas of an immersed structure within a short period.
In the present specification "comprise" means "includes or consists of and "comprising" means "including or consisting of".
The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims

An apparatus for removing marine organisms and the like by positioning of the removing apparatus in the proximity of a surface of an immersed structure, so that the removing apparatus collides with the said surface of the structure, which apparatus comprises a plurality of bodies linked to each other and a protective cover to cover the outer circumference of each body, wherein the protective cover is made of a resin having a durometer hardness ranging from 75 to 85.
The apparatus according to Claim 1, wherein the inner diameter of the protective cover is greater than the outer diameter of the body and the protective cover is held rotatably on the outer circumference of the body.
The apparatus according to Claim 1 or 2, wherein the protective cover comprises two separate cup-shaped portions respectively provided with a snap-fit projection and recess arrangement for securing the cup-shaped portions together.
The apparatus according to any one of Claims 1 to 3, wherein at least a part of a circumferential face of the protective cover comprises a plurality of bridge-like projections for colliding against a surface of the immersed structure.
The apparatus according to Claim 2 or 3, wherein at least a part of a circumferential face of the protective cover comprises a plurality of bridge-like projections which extend parallel to an axis of rotation of the protective cover.
The apparatus according to Claim 3, wherein at least a part of a circumferential face of the protective cover comprises a plurality of bridge-like projections, some or all of which are aligned with respective projections of the snap-fit arrangement.
The apparatus according to any one of Claims 1 to 6, wherein the outer circumference of said protective cover is provided with a sleeve.
The apparatus according to Claim 7, wherein the sleeve comprises an inner face adapted to fit some or all of a plurality of projections provided on the outer circumferential surface of the said protective cover.
The apparatus according to Claim 7 or 8, comprising a plurality of projections on the outer circumferential surface of said sleeve.
The apparatus according to any one of Claims 7 to 9, wherein said sleeve is made of a resin having a durometer hardness ranging from 75 to 85.
The apparatus according to any one of Claims 1 to 10, wherein a linking part of the removing apparatus has a freely rotating collar thereon.
The apparatus according to Claim 11, wherein the collar has an ellipsoid section and is tilted toward the elongated circular in across the width direction thereof.
The apparatus according to any one of Claims 1 to 12, comprising ears at two opposite locations of each body for linking the bodies together, the ears at opposite locations of a body being positioned in perpendicular planes.
The apparatus according to any one of Claims 1 to 13, wherein a first layer of the removing apparatus, that floats on the surface of the sea or water, is linked to a second layer of the removing apparatus, that is suspended from the first removing apparatus, through a linking device such as a chain, and said linking device is covered with a pipe to limit the motion of the linking device.