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

PROVISIONAL SPECIFICATION
(See section 10 and rule 13)

“THRUSTER FOR A SUBMERSIBLE VEHICLE”

By
PLANYS TECHNOLOGIES PRIVATE LIMITED
AN INDIAN COMPANY
NO. 5 JAYA NAGAR EXTENSION, BALAJI NAGAR MAIN ROAD, G.K. AVENUE, PUZHUTHIVAKKAM, CHENNAI 600091, TAMIL NADU, INDIA

THE FOLLOWING SPECIFICATION DESCRIBES THE INVENTION.

TECHNICAL FIELD OF THE INVENTION
The present invention relates to a submersible vehicle. In particular, the present invention relates to a thruster of the submersible vehicle for use in a hydrocarbon or high-temperature environment.
BACKGROUND OF THE INVENTION
Hydrocarbon processing industries, fuel stations, or chemical industries store an inflammable hydrocarbon or high-temperature fluid in large tanks. Any damage or abnormality to such tanks may lead to hazard such as explosion or fire. In order to avoid such hazards, regular and thorough inspection of tanks is essential to ensure public safety and health by identifying and addressing issues like sediment buildup, corrosion, leakage, and structural damage of the tanks. The regular inspection promotes longevity by enabling preventative maintenance and extending the lifespan of the tanks. However, inspecting and cleaning the complex interiors of these tanks presents significant challenges. This inspection involves draining tanks and deploying divers, posing safety risks and incurring downtime.
Further, unmanned submersible vehicles are known for conducting underwater inspections as they offer improved manoeuvrability in water bodies. These vehicles can be fitted with data capturing equipment, low light HD cameras, depth sensors, and altimeters which give a better idea about underwater objects. However, these vehicles generally use thrusters for propulsion. The thruster is a device which provides a thrust force for propulsion or control of the vehicle. Generally, thrusters have an electric motor that is enclosed to seal it from water, a propeller rotatably connected to the motor through a shaft. However, existing thrusters of the submersible vehicle are designed for underwater operation, since water is a good thermal sink and a non-flammable fluid. Thus, the existing thrusters cannot be readily adapted to use in inflammable or high-temperature fluid as they are designed without much thermal consideration. The existing thrusters are cooled by surrounding water; however, it is not the same case with the hydrocarbon fluids since the flash point of these fluids is very low.
In hydrocarbon storage or high-temperature fluid tanks, the temperature of the ambient fluid is very high, which may damage or affect the performance of the existing thrusters. Further, most of the hydrocarbons have a very low vapor pressure, and the fluid turns to vapor at low pressure leading to cavitation, thus the propellers may cavitate at a higher rate in the tank filled with hydrocarbon as compared to the propellers used in underwater operations. Cavitation causes a great deal of noise, vibrations, loss of efficiency, great wear on components and can dramatically shorten the propeller's life.
Therefore, there is a need in the art to provide a thruster for a submersible vehicle that overcomes at least one of the drawbacks or problems mentioned above.
SUMMARY OF THE INVENTION
In this respect, before explaining the current embodiments of a thruster for a submersible vehicle in detail, it is to be understood that the thruster for the submersible vehicle is not limited in its applications to the details of construction and arrangements of the components set forth in the following description or illustration. Those skilled in the art will appreciate that the concept of this disclosure may be readily utilized as a basis for the design of other structures, methods, and systems for carrying out the several purposes of the thruster for the submersible vehicle.
A primary object of the present invention is to provide a thruster for a submersible vehicle for use in a hydrocarbon or a high-temperature environment. Another object of this invention is to prevent the thruster from initiating fire or being explode during the operation in the hydrocarbon or the high-temperature environment.
In accordance with an aspect of the invention, a thruster for a submersible vehicle comprising: a hermetically sealed housing unit configured to house a motor unit therein, the motor unit having a driving shaft that extends along a longitudinal axis; a propeller unit hermetically connected to the housing unit, the propeller unit having a propeller shaft magnetically coupled to the driving shaft along the longitudinal axis at a stand-off distance therebetween; a cooling unit in fluidic communication with the housing unit configured to circulate a cooling fluid therein; and a controller in communication with the housing unit, the propeller unit and the cooling unit through a plurality of sensors, the controller is configured to monitor temperature and vibration of the housing unit and the propeller unit and control the circulation of the cooling fluid and a rotating speed of the blades.
In an embodiment, the propeller unit having a plurality of blades arranged radially around a propeller hub, the propeller hub is mounted on the propeller shaft.
In an embodiment, the propeller unit has a hermetically sealed chamber therein, the chamber is filled with a coolant.
In an embodiment, the blades have a reduced pitch, and the controller is configured to modify a pitch of the blades.
In an embodiment, the cooling unit is in fluidic communication with the housing unit through an inlet port and an outlet port defined on the housing unit.
In an embodiment, the cooling unit comprises a cooling fluid tank configured to inject the cooling fluid into the housing unit through the inlet port.
In an embodiment, the cooling unit comprises a pump configured to evacuate at least an ambient air or the circulated cooling fluid from the housing unit through the outlet port.
In an embodiment, the propeller unit has a first end connected to the housing unit and a nose cone is positioned on a second end.
In an embodiment, the nose cone has a plurality of arms spaced at an interval and extending from the nose cone to support an annular nozzle.
In an embodiment, the housing unit has a plurality of arms spaced at an interval and extending from the housing unit to support the annular nozzle.
In an embodiment, the annular nozzle has a minimum inner diameter larger than a diameter of the propeller blades, the annular nozzle configured to provide an inlet and an outlet for the flow of a surrounding fluid.
In an embodiment, the annular nozzle has an external surface having a linear profile inclined from the inlet to the outlet.
In an embodiment, the annular nozzle has an inner surface having a curved profile such that a diameter of the nozzle at the outlet is greater than a diameter of the nozzle at the inlet, and the diameter of the nozzle at the inlet is greater than a diameter of the nozzle at a middle portion.
In an embodiment, the motor unit is coated with an electrically insulated and thermally conductive material to prevent the motor unit being affected by the cooling fluid.
In an embodiment, the motor unit comprises a stator, and a rotor, the motor unit is in fluidic communication with the housing unit and filled with the circulating cooling fluid.
In an embodiment, the rotor has small appendages to induce rotation of the cooling fluid inside the motor unit.
In an embodiment, the propeller unit is hermetically connected to the housing unit using a seal configured to accommodate a forward and backward movement of the propeller unit with respect to the housing unit within a range of 0 to 10 mm.
In an embodiment, the propeller unit is hermetically connected to the housing unit using a telescopic connection configured to accommodate a forward and backward movement of the propeller unit with respect to the housing unit within a range of 0 to 10 mm.
In an embodiment, the housing unit has an actuation unit positioned thereon, the actuation unit has at least actuation member configured to control reciprocating movement of the propeller unit.
In an embodiment, the controller is configured to change the stand-off distance between the driving shaft and the propeller shaft by actuating the actuation unit.
In an embodiment, the nose cone has an inner space filled with the coolant, the inner space of the nose cone and the chamber of the propeller unit configured for conductive cooling of the propeller blades.
In an embodiment, the arms and the annular nozzle each has a hollow profile, and the hollow profiles are in fluidic communication with the nose cone configured for convective cooling of the propeller blades.
It is therefore important that the claims be regarded as including such equivalent construction insofar as they do not depart from the spirit and scope of the thruster for the submersible vehicle. It is also to be understood that the phraseology and terminology employed herein are for purposes of description and should not be regarded as limiting.
BRIEF DESCRIPTION OF THE DRAWING
The accompanying drawings, which are included to provide a further understanding of the invention are incorporated in and constitute a part of this specification, illustrate an embodiment of the invention and together with the description serve to explain the principles of the invention. They are meant to be exemplary illustrations provided to enable persons skilled in the art to practice the disclosure and are not intended to limit the scope of the appended claims. The detailed description is described with reference to the accompanying figures.
Figure 1 shows a perspective view of a submersible vehicle according to an embodiment of the present invention;
Figure 2 shows a perspective view of a thruster for the submersible vehicle according to an embodiment of the present invention;
Figure 3 shows another perspective view of the thruster of figure 2;
Figure 4 shows a sectional view of the thruster for the submersible vehicle according to an embodiment of the present invention; and
Figure 5 shows an isometric view of the thruster for the submersible vehicle according to an embodiment of the present invention.
Throughout the drawing, 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 the invention as defined by the description. It includes various specific details to assist in that understanding but these are to be regarded as merely exemplary. In addition, descriptions of well-known functions and constructions are omitted for clarity and conciseness.
The terms and words used in the following description are not limited to the bibliographical meanings but are merely used by the inventor to enable a clear and consistent understanding of the invention. Accordingly, it should be apparent to those skilled in the art that the following description of the present invention is provided for illustration purposes only.
It is to be understood that the singular forms “a”, “an” and “the” include plural referents unless the context clearly dictates otherwise. Here, the word “hydrocarbon environment” refers to a tank or a well or a reservoir filled with a hydrocarbon fluid or any other fluid with a higher concentration of the hydrocarbons. Here, the word “high-temperature environment” refers to a tank or a reservoir filled with a fluid having high-temperature fluid or a toxic fluid.
Figure 1 shows a three-dimensional view of a remotely operated submersible vehicle (1000) according to an embodiment of the present invention. In an embodiment, the submersible vehicle (1000) is an autonomous submersible vehicle (1000). The submersible vehicle (1000) comprises at least one thruster (100). The thrusters (100) are positioned on a frame (300) or a hull of the submersible vehicle (1000). In an embodiment, the submersible vehicle (1000) comprises a plurality of light (500) and a camera module (400) positioned on the frame (300) of the vehicle (1000). The submersible vehicle (1000) has a tether (200) that connects the vehicle (1000) to a surface vessel. The tether (200) is a cable that provides power to the vehicle (1000) and allows an operator to communicate with the vehicle (1000). In an embodiment, the tether (200) includes a plurality of hose pipes and cables. In an embodiment, the hose pipes are used to circulate a cooling fluid from the surface vessel to the submersible vehicle (1000).
The present invention provides a thruster (100) for a submersible vehicle (1000) for use in a hydrocarbon or a high-temperature environment. The submersible vehicle (1000) during an operation in the hydrocarbon or the high-temperature environment may lead to a hazard situation, such as an explosion. In order to avoid such hazardous situation, at least an element of a fire triangle should be eliminated from the thrusters. Oxygen, heat, and fuel are the three elements of the fire triangle. Explosion or fire occurs in a system, when all three elements are present at a sufficient level. The fire and explosion can be prevented by removing or eliminating at least one element of the fire triangle from the system. Thus, a further object of the present invention is to remove, eliminate or supress at least one element of the fire triangle from the thrusters (100) emerging during the operation.
Figures 2-5 shows the thruster for the submersible vehicle according to various embodiments of the present invention. The thruster (100) for the submersible vehicle (1000) comprises a hermetically sealed housing unit (10). The housing unit (10) is sealed using a plurality of static rubber seals allowing the operator to open the housing unit (10) when the thruster is not in operation. The housing unit (10) has a cable connecting end (13) configured to connect with a power source of the submersible vehicle (1000). The other units or elements present in the housing unit (10) or mounted on the thruster (100) are internally or externally in communication the cable connecting end (13) for their power requirement. The housing unit (10) houses a motor unit (20) therein. The motor unit (20) comprises a stator (22), a rotor (23) and a driving shaft (21). The driving shaft (21) is extended in a longitudinal axis (X).
The thruster further comprises a propeller unit (30) hermetically connected to the housing unit (10). In an embodiment, the propeller unit (30) is connected to the housing unit (10) using a plurality of fasteners. In an embodiment, the propeller unit (30) is hermetically connected to the housing unit (10) using a connection configured to accommodate a forward and backward movement of the propeller unit (30) with respect to the housing unit (10) within a range of 0 to 10 mm. In an embodiment, the range is 0 to 5 mm. In an embodiment, the connection is a compression seal connection or a telescopic connection. Further, the connection between the housing unit (10) and the propeller unit (30) is sealed using a plurality of static rubber seals. In an embodiment, static rubber seal is an O-ring. In an embodiment, the housing unit (10) has an actuation unit positioned on an outer periphery of the housing unit (10), the actuation unit has at least one actuation member configured to control reciprocating movement of the propeller unit (30). In an embodiment, the actuation unit is at least a hydraulic unit, a pneumatic unit, a piezoelectric unit or a ball screw unit. In an embodiment, the hydraulic unit is the actuation unit. The hydraulic unit comprises a cylinder, a rod secured to a piston, the rod and piston being slidably received within the cylinder, wherein the rod along with the piston is capable of reciprocating movement. At least one cylinder is positioned on the outer periphery of the housing unit (10). The piston rod is connected to the propeller unit (30) while maintaining the alignment of the housing unit (10) and the propeller unit (30). The hydraulic unit, when actuated, pulls the propeller unit (30) towards the housing unit (10) or pushes the propeller unit (30) away from the housing unit (10).
The propeller unit (30) has a hermetically sealed chamber (34) therein, the chamber (34) is filled with a coolant. The propeller unit (30) comprises a propeller shaft (31) and a propeller hub (32). The propeller shaft (31) is magnetically coupled to the driving shaft (21) along the longitudinal axis (X) at a stand-off distance between the driving shaft (21) and the propeller shaft (31). The driving shaft (21) is rotatably coupled to the propeller shaft (31) through a magnetic coupling (25). The magnetic coupling (25) uses an attractive force between magnets on each shaft (21, 31). The rotating magnets of the driving shaft (21) induces a magnetic field that causes the magnets on the propeller shaft (31) to rotate in alignment, effectively transmitting power across the stand-off distance. The magnetic coupling (25) transfers torque between the shafts (21, 31) without any direct physical contact and thus enables maintaining hermetic sealing to the housing unit (10). Since, the motor unit (20) is one of the leading heat generating element of the thruster (100). The surrounding fluid, i.e. hydrocarbon fluid or hot-temperature fluid, is restricted from entering the housing unit (10) and interact with the motor unit (20) in the absence of a physical shaft. Thus, the fuel element of the fire triangle, i.e. hydrocarbon fluid or hot-temperature fluid, is eliminated from the housing unit.
The propeller hub (32) is mounted on the propeller shaft (31) and a plurality of blades (33) are arranged radially around a propeller hub (32). In an embodiment, the blades (33) have a reduced pitch to minimize cavitation, vibration and noise. Additionally, to further minimize cavitation, a profile of the blades is designed to ensure that a low-pressure region in the blade (33) is not reduced below a vapor pressure of the surrounding fluid. In an embodiment, the blades (33) are optimized using a Kaplan series design considering parameters such as root diameter, profile area, propeller diameter, pitch, required thrust, and power input.
The propeller unit (30) has a first end and a second end. The first end is connected to the housing unit (10) and a nose cone (35) is positioned on the second end. The nose cone (35) has a plurality of arms (36) spaced at an interval and extending from the nose cone (35). In an embodiment, the arms (36) are spaced at regular intervals. In an embodiment, the arms (36) are extended upwards with respect to the nose cone (35) and have an inclination. The arms (36) support an annular nozzle (37). In an embodiment, the housing unit (10) has a plurality of arms (14) spaced at an interval and extending upwards from the housing unit (10) to support the annular nozzle (37). In an embodiment, the arms (14) are spaced at regular intervals. In an embodiment, the arms (14) have an inclination.
The annular nozzle (37) configured to provide an inlet (38) and an outlet (39) for the flow of the surrounding fluid. The annular nozzle (37) improves thrust performance. The annular nozzle (37) also serves as a dampened casing for the propellor unit (30). The annular nozzle (37) has a flow path defined between the inlet (38) and the outlet (39). The annular nozzle (37) has a minimum inner diameter that is slightly larger than a diameter of the blades (33). In an embodiment, the annular nozzle (37) has an external surface having a linear profile inclined from the inlet (38) to the outlet (39). In an embodiment, the annular nozzle (37) has an inner surface having a curved profile such that a diameter of the nozzle (37) at the outlet (39) is greater than a diameter of the nozzle (37) at the inlet (38), and the diameter of the nozzle (37) at the inlet (38) is greater than a diameter of the nozzle (37) at a middle portion. In an embodiment, the middle portion is defined in the between a range 0.4-0.9 times a total length of the flow path from the inlet (38). In an embodiment, the middle portion is defined in the between the range 0.6-0.9 times the total length of the flow path from the inlet (38). In an embodiment, the diameter of the nozzle (37) at the outlet (39) is greater than the diameter of the nozzle (37) at the inlet (38), and the diameter of the nozzle (37) at the inlet (38) is greater than a diameter of the nozzle (37) at a point proximal to the outlet (39). The curved profile of the inner and outer surface of the annular nozzle (37) improves thrust performance and reduces vibrations.
In an embodiment, the nose cone (35) has an inner space filled with the coolant, the inner space of the nose cone (35) and the chamber (34) of the propeller unit (30) are configured for conductive cooling of the blades (33). In an embodiment, each of the arms (14, 36) have a hollow profile, and the hollow profiles are in fluidic communication with the nose cone (35) configured for convective cooling of the blades (33). In an embodiment, the annular nozzle (37) has a hollow profile, and the hollow profile is in fluidic communication with the arms (14, 36) and the nose cone (35) configured for convective cooling of the blades (33). In an embodiment, the arms (14, 36), the nose cone (35) and annular nozzle (37) are fastened keeping their hollow profiles aligned with the inner space of the nose cone (35). In an embodiment, the arms (14, 36), the nose cone (35) and annular nozzle (37) are formed as a single component, such that the hollow profiles and the inner space are filled with the coolant through a port defined on the single component.
The thruster (100) further comprises a cooling unit and a controller (40). The cooling unit is in fluidic communication with the housing unit (10) through an inlet port (11) and an outlet port (12) defined on the housing unit (10). In an embodiment, the cooling unit is positioned on the surface vessel. In an embodiment, the cooling unit is positioned on the submersible vehicle (1000). The inlet port (11) and the outlet port (12) of the housing unit (10) are connected to the cooling unit through the hose pipes. The cooling unit is configured to circulate or purge the cooling fluid within the housing unit (10). In an embodiment, the cooling fluid is an inert gas. In an embodiment, the inert gas is at least one among nitrogen, carbon dioxide, argon and the like. During the selection of the cooling fluid, it is ensured that the cooling fluid is not combustible within the operating parameters of the motor unit (20).
The cooling unit comprises a cooling fluid tank, a pump and a treatment device. The cooling fluid tank is configured to inject the cooling fluid into the housing unit (10) through the inlet port (11). Accordingly, the housing unit (10) is internally cooled by circulating the cooling fluid and thus heat is removed heat from all the units or elements present in the housing unit (10). In an embodiment, the motor unit (20) is coated with an electrically insulated and thermally conductive material to prevent the motor unit (20) being affected by the cooling fluid. In an embodiment, the electrically insulated and thermally conductive material is an epoxy. In an embodiment, the epoxy is Loctite 1919324 Marine Epoxy or Loctite AA 324. In an embodiment, all the units, especially the electronic and the electrical units positioned in the housing unit (10) are coated with the electrically insulated and thermally conductive material to prevent them being affected by the cooling fluid.
When the ambient temperature of the surrounding fluid is high, the cooling fluid in the circulated in the housing unit (10) along a cooling path. The cooling path is defined on an inner periphery of the housing unit (10), such that an inner surface of the housing unit (10) is maintained at a lower temperature as compared to the temperature of the surrounding fluid. The cooling further ensures that the heat generated by the motor unit (20) is removed by the cooling fluid. Further, an insulation layer or an insulation coat is provided on the outer periphery of the housing unit (10). Accordingly, the heat exchange between the housing unit and the surrounding fluid is prohibited. Further, the surrounding fluid, i.e. hydrocarbon fluid or hot-temperature fluid, cannot interact with the radiating heat of the housing unit (10). Consequently, the heat element of the fire triangle is suppressed from the housing unit (10), since the inner surface of the housing unit (10) is continuously cooled by the cooling unit.
The pump of the cooling unit is configured to evacuate an ambient air from the housing unit (10) through the outlet port (12) at the initial stage. Further, once the cooling fluid is circulated in the housing unit (10), the pump evacuates the cooling fluid or a mixture of cooling fluid and the ambient air from the housing unit (10) through the outlet port (12). The treatment device of the cooling unit is configured to remove heat, air and oxygen from the evacuated fluid and then supply the treated fluid to the fluid tank. Further, the cooling fluid is re-circulated by the cooling fluid tank. Accordingly, the oxygen element of the fire triangle is eliminated or suppressed from the housing unit (10), since the pump evacuates at least the ambient air or the cooling fluid from the housing unit (10) and the treatment device removes the heat, air and oxygen from the evacuated fluid prior to re-circulation of the cooling fluid. The cooling fluid present in the housing unit (10) during the circulation exerts pressure on the inner surface of the housing unit (10) to counter the surrounding fluid pressure exerted on the outer periphery of the housing unit (10) at depth.
The motor unit (20) is in fluidic communication with the housing unit (10) and filled with the cooling fluid. In an embodiment, the rotor (23) has small appendages to induce rotation of the cooling fluid inside the motor unit (20) to enhance the cooling of the motor unit (20). In an embodiment, the stator (22), the rotor (23) and the driving shaft (21) are provided with a protective coat to prevent the motor unit (20) being affected by the cooling fluid. In an embodiment, the stator (22) and the rotor (23) are coated with the thermally conductive material. In an embodiment, the stator (22) and the rotor (23) are coated with the electrically insulated and thermally conductive material. Therefore, the heat from the stator (22) is safely dissipated. Thus, the temperature of the motor unit (20) is kept low to ensure that the temperature of the motor unit (20) does not trigger an explosion by exceeding the flash point of the surrounding fluid. In addition, the magnetic coupling (25) transmits torque between the motor unit (20) to the propeller unit (30) avoiding any physical penetrations to the housing unit (10) to support and sustain the hermetic sealing.
The controller (40) is in communication with the housing unit (10), the motor unit (20), the propeller unit (30) and the cooling unit. In an embodiment, the controller (40) is positioned inside the housing unit (10). In an embodiment, the controller (40) is coated with the electrically insulated and thermally conductive material to prevent them being affected by the cooling fluid. The controller (40) is configured to monitor various parameters of the housing unit (10), the motor unit, the propeller unit (30) and the cooling unit through a plurality of sensors such as temperature sensors, gyroscopic sensors, speed sensors, voltage sensors, current sensors and the like. The controller (40) is configured to monitor temperature and vibration of the housing unit (10) and the propeller unit (30). The controller (40) is configured to modify a volume of cooling fluid present in the housing unit (10) to counter the surrounding fluid pressure at different depths.
The controller (40) controls the circulation of the cooling fluid and rotating speed of the propeller hub (32). The controlling of the cooling fluid includes at least controlling circulation speed of the cooling fluid, controlling temperature of the cooling fluid and modifying the volume of cooling fluid present in the housing unit (10).
In an embodiment, the propeller hub (32) is a controllable pitch propeller. The controllable-pitch propeller comprises a boss that holds the blades. The blades are rotated about their vertical axis using an internal mechanism to change the pitch angle. Accordingly, the pitch can be modified by actuating the internal mechanism of the controllable pitch propeller. In an embodiment, the controller (40) is configured to modify a pitch of the blades (33). In an embodiment, the controller (40) is configured to change the stand-off distance between the driving shaft (21) and the propeller shaft (31) by actuating the actuation unit. The controlling of the rotating speed of the propeller hub (32) includes at least modifying the pitch of the blades (33), changing the stand-off distance and controlling the speed of the motor unit (20). The controlling of the rotating speed of the propeller hub (32) reduces the cavitating effect on the blade and thus dampens the vibrations and the noises arising during the cavitation. Further, the controlling of the rotating speed of the propeller hub (32) reduces vibrations sensed by the gyroscopic sensors.
Accordingly, the thruster (100) eliminates or suppresses at least one element of the fire triangle from reaching sufficient level and thus hazardous situations are prevented in the hydrocarbon or the high-temperature environment.
In an embodiment, the controller (40) is configured to monitor a real-time measurement of voltage, current, temperature and RPM of the motor unit (20). Accordingly, the controller (40) continuously monitors a performance of the motor unit (20) and employ algorithms to analyse current, RPM, temperature, and back electromotive force to detect an abnormal condition and predicting potential failures. The controller (40) triggers error codes or activates failsafe mechanisms, such as reducing or switching the power provided to the motor unit (20). This significantly enhances the thruster's safety, reliability and longevity.
In an embodiment, the housing unit (10) is designed to maintain the thrusters centre of gravity at its centre. In an embodiment, the housing unit (10) is made using a stainless steel or aluminium to ensure safety in hydrocarbon environments or the high-temperature environment. In an embodiment, the propeller unit (30) is made using a stainless steel or aluminium to ensure safety in hydrocarbon environments or the high-temperature environment. In an embodiment, the thruster (100) is made using the materials that are inert to hydrocarbons. In an embodiment, the thruster (100) is made using the stainless steel or aluminium to ensure safety in hydrocarbon environments or the high-temperature environment. In an embodiment, the thruster (100) has a several protection layers to make it explosion proof. The thruster (100) is configured to reduce the vibrations and the noise generating due to the vibrations. Further, the thruster (100) is incorporated with a plurality of oil filled high precision bearings in the housing unit (10) and the propeller unit (30) to reduce the vibrations and the noises. The housing unit (10) and the propeller unit (30) are statically and dynamically balanced to avoid rotary vibrations and enhance the thrust efficiency. In addition, the annular nozzle (37) serves as a dampened casing for the propellor unit (30) and configured to accommodate static and dynamic vibrations. In an embodiment, the thruster (100) is mounted to the submersible vehicle (1000) at the nozzle (37), thus any vibrations arising in the thruster (100) are dampened by the nozzle (37) and not transmitted to the vehicle (1000).
EXAMPLE:
Parameters Value
Performance
Rated Thrust 10 kgf (forward thrust) Nominal
8 kgf (reverse thrust) Nominal
Rated Depth 300 m
Design Lifetime (minimum) 300 hours
Physical
Diameter 161.6 mm
Length 292.5 mm
Propeller diameter 125 mm
Weight in air (with cable) 2.8 kg
Weight in water (with cable) 0.97 kg
Mounting Hole Dimensions PCD ?25.0mm, 4 x ?4.2 THRU
Magnetic Coupling Diameter 50 mm
Torque at a stand-off distance of 1 mm 6.577 Nm
Torque at at a stand-off distance of 5 mm 2.502 Nm
Electrical
Operating Voltage 48 VDC
Rated power 950 Watts
Communication Protocol UART & PWM
Inline Cable
Type Depth rated, 8-pin cable: 2-pin power, 6-pin communication.
Material Synthetic Rubber
Wire specification 16 AWG
Wet Matings >500
Although but one preferred embodiment of the invention has been illustrated, it will be obvious to those skilled in this art that other embodiments may be readily designed within the scope and teachings thereof.
Although there has been shown and described the preferred embodiment of the present invention, it will be readily apparent to those skilled in the art that modifications may be made thereto which do not exceed the scope of the appended claims. Therefore, the scope of the invention is only to be limited by the following claims.
,CLAIMS:We Claim:
1. A thruster (100) for a submersible vehicle (1000) comprising:
- a hermetically sealed housing unit (10) configured to house a motor unit (20) therein, the motor unit (20) having a driving shaft (21) that extends along a longitudinal axis (X);
- a propeller unit (30) hermetically connected to the housing unit (10), the propeller unit (30) having a propeller shaft (31) magnetically coupled to the driving shaft (21) along the longitudinal axis (X) at a stand-off distance therebetween, the propeller unit (30) having a plurality of blades (33) arranged radially around a propeller hub (32), the propeller hub (32) is mounted on the propeller shaft (31);
- a cooling unit in fluidic communication with the housing unit (10) configured to circulate a cooling fluid therein; and
- a controller (40) in communication with the housing unit (10), the propeller unit (30) and the cooling unit through a plurality of sensors, the controller (40) is configured to monitor temperature and vibration of the housing unit (10) and the propeller unit (30) and control the circulation of the cooling fluid and a rotating speed of the blades (33).
2. The thruster (100) as claimed in claim 1, wherein the propeller unit (30) has a hermetically sealed chamber (34) therein, the chamber (34) is filled with a coolant.
3. The thruster (100) as claimed in claim 1, wherein the blades (33) have a reduced pitch, and the controller (40) is configured to modify a pitch of the blades (33).
4. The thruster (100) as claimed in claim 1, wherein the cooling unit is in fluidic communication with the housing unit (10) through an inlet port (11) and an outlet port (12) defined on the housing unit (10).
5. The thruster (100) as claimed in claim 4, wherein the cooling unit comprises a cooling fluid tank configured to inject the cooling fluid into the housing unit (10) through the inlet port (11).
6. The thruster (100) as claimed in claim 5, wherein the cooling unit comprises a pump configured to evacuate at least the circulated cooling fluid or an ambient air from the housing unit (10) through the outlet port (12).
7. The thruster (100) as claimed in claim 2, wherein the propeller unit (30) has a first end connected to the housing unit (10) and a nose cone (35) is positioned on a second end.
8. The thruster (100) as claimed in claim 7, wherein the nose cone (35) has a plurality of arms (36) spaced at an interval and extending from the nose cone (35) to support an annular nozzle (37).
9. The thruster (100) as claimed in claim 8, wherein the housing unit (10) has a plurality of arms (14) spaced at an interval and extending from the housing unit (10) to support the annular nozzle (37).
10. The thruster (100) as claimed in claim 8, wherein the annular nozzle (37) has a minimum inner diameter larger than a diameter of the blades (33), the annular nozzle (37) configured to provide an inlet (38) and an outlet (39) for the flow of a surrounding fluid.
11. The thruster (100) as claimed in claim 10, wherein the annular nozzle (37) has an external surface having a linear profile inclined from the inlet (38) to the outlet (39).
12. The thruster (100) as claimed in claim 10, wherein the annular nozzle (37) has an inner surface having a curved profile such that a diameter of the nozzle (37) at the outlet (39) is greater than a diameter of the nozzle (37) at the inlet (38), and the diameter of the nozzle (37) at the inlet (38) is greater than a diameter of the nozzle (37) at a middle portion.
13. The thruster (100) as claimed in claim 1, wherein the motor unit (20) is coated with an electrically insulated and thermally conductive material to prevent the motor unit (20) being affected by the cooling fluid.
14. The thruster (100) as claimed in claim 1, wherein the motor unit (20) comprises a stator (22), and a rotor (23), the motor unit (20) is in fluidic communication with the housing unit (10) and filled with the circulating cooling fluid.
15. The thruster (100) as claimed in claim 14, wherein the rotor (23) has small appendages to induce rotation of the cooling fluid inside the motor unit (20).
16. The thruster (100) as claimed in claim 1, wherein the propeller unit (30) is hermetically connected to the housing unit (10) using a connection configured to accommodate a forward and backward movement of the propeller unit (30) with respect to the housing unit (10) within a range of 0 to 10 mm.
17. The thruster (100) as claimed in claim 16, wherein the housing unit (10) has an actuation unit positioned thereon, the actuation unit has at least one actuation member configured to control reciprocating movement of the propeller unit (30).
18. The thruster (100) as claimed in claim 17, wherein the controller (40) is configured to change the stand-off distance between the driving shaft (21) and the propeller shaft (31) by actuating the actuation unit.
19. The thruster (100) as claimed in claim 8, wherein the nose cone (35) has an inner space filled with the coolant, the inner space of the nose cone (35) and the chamber (34) of the propeller unit (30) configured for conductive cooling of the blades (33).

20. The thruster (100) as claimed in claim 19, wherein the arms (14, 36) and the annular nozzle (37) each having a hollow profile, and the hollow profiles are in fluidic communication with the nose cone (35) configured for convective cooling of the blades (33).
Dated this 13th day of March, 2025
For PLANYS TECHNOLOGIES PVT. LTD.
By their Agent

(D. MANOJ KUMAR) (IN/PA-2110)
KRISHNA & SAURASTRI ASSOCIATES LLP