GB2038721A

GB2038721A - Apparatus for cleaning ship's hulls

Info

Publication number: GB2038721A
Application number: GB7846834A
Authority: GB
Original assignee: Bingham V P
Current assignee: Bingham V P
Priority date: 1978-12-01
Filing date: 1978-12-01
Publication date: 1980-07-30

Abstract

Apparatus (2) for cleaning the submerged sides of a ship (6) which is underway comprises cleaning means (8, 10) and a depth varying arrangement (14) which is controlled by a water pressure sensor (12) to cause the apparatus (2) automatically to rise and dive. Preferably the cleaning means comprises a pair of brushes which are rotated by water flowing therethrough. <IMAGE>

Description

SPECIFICATION Apparatus for cleaning the submerged sides of a ship This invention relates to apparatus for cleaning the submerged sides of a ship whilst the ship is moving.

It is well known that the submerged sides of ships become fouled with marine life. Vegetable fouling tends to occur mainly on those parts of the ship's sides that receive some sunlight. Animal fouling tends to occur at greater depths on the ship's side, for example on the underside of the ship's hull, where light does not readily penetrate and where darkness prevails. The animal fouling tends to occur most when the ship is stationary. With large tankers and bulk carriers, these ships are stationary for only a short part of their working life so that animal fouling is much less of a problem than the vegetable fouling which occurs all the time.

It is known to remove vegetable fouling with scrubbing devices which are either operated under water by a diver or which are operated remotely by means of a camera on a work boat. The ship being cleaned is required to be stationary so that whilst the ship is being cleaned, time is lost during which the ship could otherwise be operational. A device is also known for cleaning the submerged sides of a ship whilst the ship is moving but this device requires a considerable amount of manual control from the ship's deck in order to cause the device to move up and down along the ship's submerged sides. The device is therefore unsatisfactory in that it requires too much attendance from operating personnel.

It is an aim of the present invention to provide apparatus for cleaning the submerged sides of a ship whilst the ship is moving, the apparatus not being subject to the above mentioned disadvantages.

Accordingly, this invention provides apparatus for cleaning the submerged sides of a ship whilst the ship is moving, which apparatus comprises cleaning means, a water pressure sensor, and a depth varying arrangement, the water pressure sensor being effec tire to control the depth varying arrangement, and the depth varying arrangement being effective in use of the apparatus to cause the apparatus automatically to rise and dive.

The apparatus of the present invention may be used for cleaning various types and sizes of ships such for example as tankers, bulk carriers and liners.

The apparatus may be secured to the ship by a line and the apparatus can be paid out or hauled in by a winch. The depth varying arrangement then operates with the line to cause the apparatus to move overhe submerged sides of the ship along an up-and-down zig-zag path.

The c'eaning means may comprise one or more brushes. Dreferably, the cleaning means comprises a pair of rotary brushes. Advantageously, these brushes are adapted to rotate in opposite directions.

The brushes may be adapted to be rotated by the water through which the ship is passing. Alternatively, the brushes may be adapted to be rotated by an electric, hydraulic or pneumatic device.

If desired, alternative cleaning means may be employed in the apparatus of the invention. Thus, for example, the cleaning means may also comprise a device for emitting one or more jets of water. Such a device for emitting one or more jets of water may also be used in conjunction with the cleaning brushes if desired.

Various types of water pressure sensor may be used in the apparatus of the invention. Generally, they may be mechanical and/or electrical in construction. By way of example only, it is mentioned that the water pressure sensor may include a first bellows device which is sensitive to water pressure.

Advantageously, the first bellows device controls the passage of water to a second bellows device, the water controlling the operation of the second bellows device, and the second bellows device forming part of the depth varying arrangement. Preferably, the second bellows device is spring biased.

If desired, the water pressure device or the second bellows may also be gas piston and cylinder arrangements.

Preferably, the depth varying arrangement includes one or more vanes but it is to be appreciated that other depth varying arrangements may be employed if desired.

Advantageously, the apparatus of the invention includes biasing means for biasing the apparatus into contact with the submerged sides of the ship.

Preferably, the biasing means comprises one or more vanes.

The apparatus of the invention may also include if desired one or more vanes for counteracting the effects of the changing angle of pull of the line, for example a tow rope or cable, employed to cause the apparatus to move along the submerged sides of the ship.

Embodiments of the invention will now be described solely by way of example and with reference to the accompanying drawings in which: Figure 1 is an isometric view of apparatus in accordance with the invention; Figure 2 is a diagrammatic side view of the apparatus illustrated in Figure 1; Figure 3 is a cross section on the line I - II of the apparatus shown in Figure 2; Figure 4 is a diagrammatic plan view of the apparatus; Figure 5 shows part of the apparatus illustrated in Figure 1; Figure 6 shows in detail one form of depth varying arrangement that can be used in the apparatus illustrated in Figure 1; Figure 7shows a possible supplementary control vane arrangement that may be used in the apparatus illustrated in Figure 1; and Figure 8 is a side elevation showing the apparatus of the invention in use.

Referring to the drawings, there is shown apparatus 2 for cleaning the submerged side 4 of a ship 6 whilst the ship 6 is moving. The apparatus 2 comprises cleaning means 8, 10 which are shown most clearly in Figure 5, a water pressure sensor 12, one example of which is shown in Figure 6, and a depth varying arrangement 14, one example of which is also shown in Figure 6. Itwill be explained in more detail herein below that the water pressure sensor 12 is effective to control the depth varying arrangement 14, and the depth varying arrangement 14 is effective to cause the apparatus 2 to move over the submerged side 4 of the ship 6 along an up-and-down zig-zag path.

The cleaning means 8, 10 each comprise bristles 16 which are mounted on the free ends of curved blades 18, the blades 18 extending outwardly from a central tubular member 20 which is supported on a shaft 22. The shaft 22 extends from a spider 24 which is positioned in an opening 26 in a housing 28, the housing 28 containing the cleaning means 8 or 10. In operation of the apparatus 2, water passes through the opening 26 and over the spider 24 and it causes the blades 18 to rotate in the housing 28 and the bristles 16 then scrub the side 4 of the ship 6.

As shown most clearly in Figures 1,2 and 6, the apparatus 2 has a depth varying arrangement 14 which includes a pair of vanes 30, 32. The vanes 30, 32 pivot up and down about axes 34, 36 respectively which are substantially perpendicular to the side 4 of the ship 6. Referring especially to Figure 2, when the vanes 30, 32 are set in the position indicated by the dotted line A, then the apparatus 2 is caused to rise, and when the vanes 30, 32 are set in the position indicated by the dotted line B, then the apparatus 2 is set to dive.

As indicated most clearly in Figure 6, the vanes 30, 32 are operated by a bellows and mechanical linkages which also form part of the depth varying arrangement 14. More specifically, a pair of arms 35, 37 are connected to the illustrated vane 30 and the arm 37 terminates in a plate 38. The plate 38 supports a bellows 40 and a compression spring 42 is provided in the bellows 40. The bellows 40 is gas filled and it operates in a cylinder 44 which can have water introduced into it or water removed from it by means of a pipe 46. The pipe 46 connects to a spool and valve device 48 which comprises a rod spool 50 operating in a cylinder 52. The rod spool 50 is provided with two apertures 54, 56 and these apertures can be aligned with an inlet outlet pipe 58.

As shown in Figure 6, one end of the rod spool 50 is connected to a spring 60 and the other end of the rod spool 50 is connected to the water pressure sensor 12.

The water pressure sensor 12 comprises a gas filled bellows 62 which is anchored at its end remote from the rod spool 50 to an anchorage point 64. The length of the bellows 62 varies depending upon the pressure acting on it, this pressure in turn being de:endent upon the height of the water above the bellows 62. The length of the bellows 62 is effective to control the position of the apertures 54, 56 with respect to the orifice 58 so that water can be introduced or removed from the cylinder 44. The pressure of the water in the cylinder 44 is effective to control tne length of the bellows 40 and this in effect moves the arm 37 into and out of the cylinder 44 as required to appropriately control the angle of inclination of the vane 30.The cylinder 44 becomes filled with water under pressure at a pre-determined changeover depth, thereby causing compression of the bellows 40 which sends the vane 30 to its rise in position A. At zero depth but with the sensor still immersed, the vane 30 is moved to its dive position B by reducing the water pressure in the cylinder 44 via the pipes 46, 58, thereby allowing the bellows 40 to expand under the influence of the spring 42. The zero and maximum changeover depth settings of the valve device 48 can be varied by adjusting the length of the rod spool 50 by means of an adjusting device 51 andior by adjusting the tension in the spring 60.

Referring now back to Figures 1 and 4, it will be seen that the apparatus 2 is provided with biasing means in the form of a pair of vanes 64,66 for biasing the apparatus 2 into contact with the side 4 of the ship 6. It will be seen that these vanes 64,66 pivot in a plane perpendicular to the plane in which the vanes 30, 32 pivot.

The vanes 30,32,64,66 are mounted in a frame 68 which is adapted to slide along the side 4 of the ship 6. The frame 68 is provided with rollers 70,72 as illustrated in Figures 3 and 4 for enabling the apparatus 2 to slide easily up and down the side 4 of the ship 6. The frame 68 is also provided with towing eyes 74, 76 for receiving towing ropes 78, 80 respectively.

If the apparatus 2 is being towed along the side 4 of the ship 6 by the towing rope 78, then this towing rope may exert some pull at varying angles on the apparatus 2 which may tend to upset the balance provided by the vanes 30, 32. This variation of direction of pull by the tow rope 78 can be counteracted by means of a vane 82 which is connected by means of levers 84, 86, 88 to the towing eye 74. A spring 90 as illustrated in Figure 7 can also be provided to assist in the appropriate movement of the vane 82.

Referring now especially to Figure 8, the towing pattern made by the apparatus 2 over the side 4 of the ship 6 is illustrated. More specifically, there is shown a towing pattern 92 for a first pass of the apparatus 2, a towing pattern 94 for an intermediate pass of the apparatus 2 and a towing pattern 96 for a final pass of the apparatus 2. Figure 8 also shows that the tow line 78 can be paid out or hauled in from a winch 98.

Since the apparatus 2 enables the submerged sides of the ship to be cleaned easily whilst the ship is in motion, it will be appreciated that the submerged sides of the ship can be frequently cleaned.

This will avoid the build-up of vegetable fouling so that the submerged sides of the ship can be very lightly scrubbed by the bristles 16. This light scrubbing will prevent undue abrasion of the sides of the ship and in particular it will avoid or reduce the removal of the anti-fouling paint that is usually provided on the sides of the ship. The drag on the ship's passage through the water due to the animal fouling can thus always be kept to a minimum so that unnecessary fuel is not consumed in overcoming this drag.

It is to be appreciated that the embodiments of the invention described above have been given by way of example only and that modifications may be effected. Thus, for example, the auxiliary vane 82 could be omitted if desired. The illustrated brush cleaning means 8, 10 could be replaced or au gmented with water jet cleaning means. Other types of water pressure sensor could be employed including a gas piston and electrical devices and they could act directly on the vanes 30, 32. The blades 18 may be of decreasing pitch and they may have means for compensating for wear of the bristles 16.

Claims

1. Apparatus for cleaning the submerged sides of a ship whilst the ship is moving, which apparatus comprises cleaning means, a water pressure sensor, and a depth varying arrangement, the water pressure sensor being effective to control the depth varying arrangement, and the depth varying arrangement being effective in use of the apparatus to cause the apparatus automatically to rise and dive.

2. Apparatus according to claim 1 in which the cleaning means comprises one or more brushes.

3. Apparatus according to claim 1 or claim 2 in which the cleaning means comprises a pair of rotary brushes.

4. Apparatus according to any one of the preceding claims in which the brushes are adapted to be rotated by the water through which the ship is passing.

5. Apparatus according to any one of claims 1 to 3 in which the brushes are adapted to be rotated by an electric, hydraulic or pneumatic device.

6. Apparatus according to claim 1 in which the cleaning means is a device for emitting one or more jets of water.

7. Apparatus according to any one of the preceding claims in which the water pressure sensor includes a first bellows device which is sensitive to water pressure.

8. Apparatus according to claim 7 in which the first bellows device controls the passage of water to a second bellows device, the water controlling the operation of the second bellows device, and the second bellows device forming part of the depth varying arrangement.

9. Apparatus according to claim 8 in which the second bellows device is spring biassed.

10. Apparatus according to claim 8 or claim 9 in which the first bellows device or the second bellows device is a gas piston and cylinder arrangement.

11. Apparatus according to any one of the preceding claims in which the the depth varying arrangement includes one or more vanes.

12. Apparatus according to any one of the preceding claims including biasing means for biasing the apparatus into contact with the submerged sides of the ship.

13. Apparatus according to claim 12 in which the biasing means comprises one or more vanes.

14. Apparatus according to any one of the preceding claims including one or more vanes for counteracting the effects of the changing angle of pull of a line employed to cause the apparatus to move along the submerged sides of the ship.

15. Apparatus for cleaning the submerged sides of a ship whilst the ship is moving, substantially as herein described with reference to the accompanying drawings.