Description:F O R M 2
THE PATENTS ACT, 1970
(39 of 1970)
The Patent Rule, 2003

COMPLETE SPECIFICATION
(See section 10 and rule 13)

“MOUNTING MECHANISM TO HOLD A CLEANING DEVICE ON AN UNDERWATER CARRIER”
By
Planys Technologies Private Limited
An Indian company
No. 5, Balaji Nagar Main Road, Jaya Nagar Extension,
Puzhuthivakam, Chennai - 600091
Tamil Nadu, India

The following specification particularly describes the invention and the manner in which it is to be performed
FIELD OF THE INVENTION
The present invention relates generally to mounting mechanism and, in particular to a mounting mechanism for mounting hull cleaning devices on an underwater carrier.
BACKGROUND OF THE INVENTION
Cleaning of biofouling on ship hulls is found to be a lucrative market with a large demand. Due to this demand, a myriad of solutions are available in the market – ranging from remotely operated systems to systems operated by divers. Cleaning systems with professional divers can be very slow, harmful to the operator among other disadvantages with the usage of divers, therefore, remotely operated or autonomous systems are gaining traction recently.
A variety of cleaning technologies are available in the market. They can be broadly classified into mechanical cleaning, hydrodynamic cleaning and laser cleaning. In mechanical cleaning, a rotary brush with special bristles is used. These are often driven by a hydraulic drive and carried by either a driver or a remotely operated vehicle. This method of cleaning has several disadvantages; some of the disadvantages are: existing coating on the hull may be peeled off during the cleaning process, and the bristles may get worn off often, so it will need frequent replacement. In this regard, hydrodynamic cleaning, which involves cleaning of marine biofouling with the help of a high-pressure water jet through a nozzle, most often mounted on a rotary mount. This is superior to the mechanical cleaning as this method does not remove the paint coating on the hull surface during the cleaning process. Also, with this method, a hydrodynamic suction is also possible to achieve when the nozzles are mounted on a rotary table. Therefore, this is the most preferred mode of cleaning among hull cleaning professionals.
Nevertheless, these methods are sometimes used in combination with a specially designed remotely operated vehicle or a diver. Diver operated devices are simple and often requires only one diver to operate the equipment. However, remotely operated vehicles are more complex, often in the form of a specially designed machine with track belts aided with suction devices to attach itself to the hull surface. Some remotely operated vehicles even deploy special dynamic arrangements to improve performance.
Although several hull cleaning systems exist in the market, remotely operated systems are very bulky and are often specially developed machines which results in both high operational costs and development costs. These equipment often would require a separate support vessel to support its operation. Therefore, the cost of hull cleaning, with remotely operated systems, is very high for the end user. This lead many ship owners in the commercial space resort to manual diving companies for ship hull cleaning. Also, the efficacy of the hull cleaning autonomous/remotely operated systems are yet to be proven. However, a diver-based cleaning operation can be slow, harmful (to the diver) and also inefficient.
Hence, a cleaning device as used by the diver, if mounted on existing remotely operated vehicles would significantly reduce the developmental costs. Since a diver is directly replaced by an existing remotely operated vehicle as carrier, the developmental cost is minimal. This said, it may not be straightforward to perform this switch. This would require a specially designed mounting mechanism to mount the cleaning apparatus on the remotely operated vehicle platform. The present invention address to provide the same.
OBJECTIVE OF THE INVENTION
These objectives are provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. These objectives are not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.
An important objective of the invention aims at providing a mounting mechanism to overcome the shortcomings of the above-mentioned systems.
Another objective of the present invention is to provide a modular mounting mechanism for any hull cleaning equipment such as a water-jet based multi-nozzle cleaning device or a brush-based cleaning device or any other hull cleaning devices to be mounted on remotely operated vehicles
Yet another objective of the present invention is to not affect the static-stability of the carrier when the cleaning equipment is mounted on it.
Further objective of the current invention is to not transmit impact forces to the carrier during the cleaning operation.
Yet another objective of the current invention is to provide the mounting mechanism which allow a degree of rotation for the cleaning device to enable cleaning of the ship hull’s side walls and the underside.
Another objective of the current invention is to enable the cleaning operation to be conducted while the carrier is afloat while the cleaning device by itself or the frame of the mounting mechanism has suction methods to attach itself to the ship hull.
Object of the present invention is not limited to the above-mentioned problem. Other technical problems that are not mentioned will become apparent to those skilled in the art from the following description.
SUMMARY OF THE INVENTION
According to an aspect of the invention, a mounting mechanism for mounting hull cleaning devices on an underwater carrier is disclosed. The mounting mechanism comprises a frame formed of an assembly of tubular channels, configured with a plurality of buoyancy means on both sides of the frame, a shaft assembly having a hollow shaft mounted on the frame through a plurality of bearing housings and bearings, a hinge connecting the cleaning device to the frame through the rotatable hollow shaft held in a bearing, and a mounting plate coupled at each end of the frame to mount the frame on the underwater carrier. The mounting mechanism is constructed to have the center of gravity and center of buoyancy at the same point.
Other aspects and advantages of the invention will become apparent from the following description, taken in conjunction with the accompanying drawing, illustrating by way of example the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described in greater detail with reference to an embodiment which is illustrated in the drawing figures:
Figure 1 is an illustration showing (a) isometric view, (b) front view of mounting mechanism holding a cleaning device on an underwater carrier, according to an embodiment of the present invention;
Figure 2 is an illustration showing (a) isometric view, (b) front view of mounting mechanism with a water jet based cleaning device, according to an embodiment of the present invention;
Figure 3 is an illustration is an illustration showing (a) details of the shaft assembly, (b) sectional view of the shaft assembly, according to an embodiment of the present invention;
Figure 4 is an illustration of the mounting mechanism with a compliant hinge to mount the cleaning device, according to an embodiment of the present invention; and
Figure 5 is an illustration showing the mounting mechanism with a shock absorber, according to an embodiment of the present invention.
Persons skilled in the art will appreciate that elements in the figures are illustrated for simplicity and clarity and may have not been drawn to scale. For example, the dimensions of some of the elements in the figure may be exaggerated relative to other elements to help to improve understanding of various exemplary embodiments of the present disclosure.
Throughout the drawings, it should be noted that like reference numbers are used to depict the same or similar elements, features, and structures.
DETAILED DESCRIPTION OF THE INVENTION
The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of exemplary embodiments of the invention. It includes various specific details to assist in that understanding but these are to be regarded as merely exemplary. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope and spirit of the invention. In addition, descriptions of well-known functions and constructions are omitted for clarity and conciseness.
The present invention discloses about a mount for coupling carrier vehicle and the hull cleaning devices.
The cleaning device described hereof, could be a mechanical device such as a brush, or a hydrodynamic equipment such as a water-jet based cleaning (may or may not include cavitation principles) or a laser-based cleaning equipment. However, the mounting mechanism of the present invention is not restricted to any particular cleaning equipment. The principle described by this invention can be used by a skilled person to adapt the mounting accordingly.
Figures 1-6 shows various views of a mounting mechanism (100) configured to hold a cleaning device (200) on an underwater carrier (300) like remotely operated vehicle. The mounting mechanism (100) comprises a frame (102) formed of an assembly of tubular channels, configured with a plurality of buoyancy means (104) on the frame (102), a shaft assembly (108) having a hollow shaft (110) mounted on the frame (102) through a plurality of bearing housings (112) and bearings (114), a hinge (116) connecting the cleaning device (200) to the frame (102) through the rotatable hollow shaft (110) held in a bearing (114), and a mounting plate (118) coupled at each end of the frame (102) to mount the frame (102) on the underwater carrier (300). The mounting mechanism (100) is constructed to have the center of gravity and center of buoyancy at the same point.
In a frame (102) the tubular channels should be strong and the frame material should be sufficiently stiff to hold the cleaning device/equipment (200) to the carrier (300) like ROV against gravitational, dynamic and cleaning forces. The frame (102) can be made of a lightweight and high-strength material such as but not limited to carbon fiber. Similarly, a frame (102) constructed from other materials can be used.
The buoyancy means (104) according to the present invention can be but not limited to buoyancy foams and deadweights. The center of buoyancy and center of gravity of the entire assembly is brought on the same point /close to each other by providing buoyancy foams and deadweights at different locations on the frame (102).
Plurality of bearing housings (112) and bearings (114) holds the hollow shaft (110) on the frame (102). Bearings (114) can be needle bearings and/or thrust sleeve bearings. The said bearing (114) can be plastic bearing employed in harsh environments or can be a traditional stainless-steel bearing, depending on the end use. The hollow shaft (110) in the shaft assembly (108) allows passage (122) for water flow during cleaning operation. Illustrations of the shaft assembly (108) along with its sectional view is shown in figure 3.
A hinge (116) which connects the cleaning device (200) to the frame (102) through the rotatable hollow shaft (110) can be a compliant hinge (116). Hinge (116) may be designed to be made of a flexible material and shape depending on the characteristics of the cleaning device (200). In an embodiment, a rubber dog-boned shaped hinge (116) is shown in figure 4. The hinge (116) in the form of a rubber dog-boned shape is flexible enough to cause coupling and provide flexible movement to the cleaning device (200).
The compliant hinge (116) according to the present invention provides easier alignment of the cleaning equipment (200) on the cleaning surface avoiding drooping of the cleaning equipment (200) while the carrier (300) is swimming around the ship hull.
According to an embodiment of the present invention, each end of the frame (102) is provided with a mounting plate (118) to configure the frame (102) on the underwater carrier (300) like remotely operated vehicle. This mounting plate (118) may allow minor compliancy to allow the shock loads to be dampened before it reaches the remotely operated vehicle (300).
The mounting mechanism (100) further comprises a mechanical stopper (120) provided on the frame (102) to avoid excessive rotation of the cleaning device (200). The maximum rotatable angle of the cleaning device (200) can be in the range of 90-120 degrees in the vertical plane. Mechanical stopper (120) ensures that the cleaning device (200) is not rotated excessively than set limitation.
According to an embodiment of the invention, between the frame (102) of the mounting mechanism (100) and the remotely operated vehicle (300) configured is a shock absorber (106) to dampen the shock loads and to assist in alignment of the cleaning device (200) with the ship hull. The shock absorber (106) may also protect the cleaning equipment (200) and the ROV (300) against unforeseen impacts during operations. Figure 5 shows the mounting mechanism (100) with a shock absorber (106), according to an embodiment of the present invention.
According to an embodiment of the invention, the mounting mechanism (100) may deploy a spring or an elastic member to enable the cleaning equipment (200) to return to its home position.
According to an embodiment of the present invention, the cleaning device (200) is a mechanical device such as a brush, or a hydrodynamic equipment such as a water-jet based cleaning or a laser-based cleaning equipment.
According to an embodiment of the invention, the mounting mechanism (100) employed to hold the cleaning equipment (200) is not only limited to remotely operated vehicle as the carrier vehicle (300). The mounting mechanism (100) can be adapted to be mountable on an autonomous underwater vehicle or other underwater/above-surface vehicles.
According to an embodiment of the present invention, the cleaning device (200) is mounted on a rotatable hollow shaft (110) held in a bearing (114) (see figure 2). This is to aid in alignment of the cleaning device (200) to the ship hull surface. Ship hulls can have steep curvatures at some locations. The shaft assembly (108) assists alignment of the cleaning device (200) on such curvatures. Bearing arrangement allows free rotation of the cleaning equipment (200) as a whole to assist its alignment against the cleaning surface.
According to an embodiment of the invention, the cleaning device (200) may have alignment pins to assist its alignment to high curvature ship hull surfaces. The alignment pins may also be replaced with a tripod-configuration of wheels on the cleaning device. Alternatively, magnetic devices may also be used to assist alignment.
The mounting mechanism can be employed for any hull cleaning equipment such as a water-jet based multi-nozzle cleaning device or a brush-based cleaning device or any other hull cleaning devices to be mounted on remotely operated vehicles.
The mounting mechanism provides the advantages that the static-stability of the ROV is not affected when the cleaning equipment is mounted on it. Also, the mounting mechanism does not transmit impact forces to the ROV during the cleaning operation.
The mounting mechanism of the present invention finds application to clean the submerged portion of the ship hull, ship hull’s side walls and the underside with a ROV. Additionally, the mounting mechanism allow a degree of rotation for the cleaning device. The mounting mechanism also enables cleaning operation to be conducted while the ROV is afloat and the cleaning device by itself or the frame of the mounting mechanism has suction methods to attach itself to the ship hull.
In the above detailed description, reference is made to the accompanying drawings that form a part thereof, and illustrate the best mode presently contemplated for carrying out the invention. However, such description should not be considered as any limitation of scope of the present unit. The structure thus conceived in the present description is susceptible of numerous modifications and variations, all the details may furthermore be replaced with elements having technical equivalence. In practice the materials and dimensions may be any according to the requirements, which will still be comprised within its true spirit. The embodiments shown herein are only exemplary. And further embodiments are possible within the scope of the invention.
, Claims:
1. A mounting mechanism (100) to hold a cleaning device (200) on an underwater carrier (300), the mounting mechanism (100) comprising:
a frame (102) formed of an assembly of tubular channels, the frame (102) configured with a plurality of buoyancy means (104) therein;
a shaft assembly (108) having a hollow shaft (110) mounted on the frame (102) through a plurality of bearing housings (112) and bearings (114);
a hinge (116) connecting the cleaning device (200) to the frame (102) through the shaft assembly (108); and
a mounting plate (118) coupled at each end of the frame (102) to mount the frame (102) on the underwater carrier (300);
wherein the mounting mechanism (100) is constructed to have the center of gravity and center of buoyancy at the same point.
2. The mounting mechanism (100) as claimed in claim 1, wherein the buoyancy means (104) are buoyancy foams and deadweights.
3. The mounting mechanism (100) as claimed in claimed 1, wherein the hinge (116) is in the form of a rubber dog-boned shape.
4. The mounting mechanism (100) as claimed in claimed 1, wherein the cleaning device (200) is a mechanical device such as a brush, or a hydrodynamic equipment such as a water-jet based cleaning or a laser-based cleaning equipment.
5. The mounting mechanism (100) as claimed in claimed 1, further comprises a mechanical stopper (120) provided on the frame (102) to avoid excessive rotation of the cleaning device (200).
6. The mounting mechanism (100) as claimed in claimed 5, wherein the cleaning device (200) is rotatable at angle in the range of 90-120 degrees along the vertical plane.
7. The mounting mechanism (100) as claimed in claimed 1, wherein between the frame (102) and the carrier (300) configured is a shock absorber (122) to dampen the shock loads and to assist in alignment of the cleaning device (200) with the ship hull.
8. The mounting mechanism (100) as claimed in claimed 1, wherein the cleaning device (200) has alignment pins to assist its alignment to high curvature ship hull surfaces.
9. The mounting mechanism (100) as claimed in claimed 1, is provided with a spring or an elastic member to enable the cleaning equipment (200) to return to home position.
 
10. The mounting mechanism (100) as claimed in claimed 1, wherein the underwater carrier (300) is a remotely operated vehicle or autonomous vehicle.