WO2009065874A2

WO2009065874A2 - Pneumatic electrically powered boat with pressurised compartment for battery

Info

Publication number: WO2009065874A2
Application number: PCT/EP2008/065870
Authority: WO
Inventors: Guido Enrico Grugnola
Original assignee: Guido Enrico Grugnola
Priority date: 2007-11-23
Filing date: 2008-11-19
Publication date: 2009-05-28
Also published as: ITMI20070389U1; WO2009065874A3

Abstract

An electrically powered boat (1) is described comprising a hull (2) having at least one deformable inflatable tubular portion (13) closed and sealed by a rigid hull bottom portion (3) to form a single closed pressurised chamber (100), and at least one electric motor (4) supplied by at least one battery (6). The battery (6) and the relative electrical equipment are located inside said closed pressurised chamber (100).

Description

"Semi-pneumatic electrically powered boat with pressurised internal battery".

DESCRIPTION The present invention concerns a semi-pneumatic electrically powered boat with pressurised battery and electrical equipment.

Inflatable boats with non-electrical propulsion are known, which typically operate with outboard internal combustion engines, mounted on the transom. These boats have the characteristic of having bulky engines and fueltanks, and of being noisy and non-eco-friendly, generating acoustic and environmental pollution.

The above-mentioned disadvantages may be unacceptable both for reasons of personal environmental conscience, and for reasons relating to objective restrictions on access connected with areas of outstanding natural value, such as protected natural areas and marine reserves. To visit these areas, it is felt to be necessary to use small craft like "tenders", i.e. dinghies serving larger vessels which are left at anchor. The high cost of running internal combustion engines and the limited space on board because of the bulk of the engines and fueltanks are a reason for seeking a more appropriate solution.

A typical solution is therefore to use vessels of small dimensions which employ ecocompatible forms of propulsion. One option may be to use an electric motor; up to now, this has been of the outboard type, and has performed its task with a typical disadvantage: the outboard electric motor's lack of performance compared with the corresponding internal combustion engine, and the problems relating to the use of batteries, electric motors and connections in a marine environment (corrosion of the metal parts and current dispersion), substantially without reducing encumbrance, which is due to the batteries, the connections and the outboard motor being mounted on the transom. The object of the present invention is therefore to create an electrically powered boat in which the apparatus for energy storage (batteries) and propulsion (electric motor), together with the relative electrical connections, are completely protected from the marine environment and are eliminated from the boat's deck in order to be able to make full use of the already limited load capacity of a boat of the type described above.

According to the invention, this object is achieved by means of an electrically powered boat comprising a hull having at least one deformable inflatable tubular portion closed and sealed by a rigid hull bottom portion to form at least one closed pressurised chamber, at least one electric motor supplied by at least one battery, characterised in that the battery and the relative electrical equipment are located inside said closed pressurised chamber.

Advantageously the limited performance of electrically powered pneumatic boats can be improved by reducing the hydrodynamic resistance of the hull, or by reducing the wetted surface area of the hull.

These and other characteristics of the present invention will be made more clearly evident from the following detailed description of an example of an embodiment of it, illustrated without limiting effect in the attached drawings, in which: figure 1 shows a partial schematic lateral view of a semi-pneumatic boat according to a first embodiment of the invention; figure 2 shows a view in section along the line H-II in figure 1 ; figure 3 shows a view in section along the line III -III in figure 1 ; figure 4 shows a partial schematic lateral view of a semi-pneumatic boat according to a second embodiment of the invention; figure 5 shows a view in section along the line V-V in figure 4; figure 6 shows a view in section along the line VI-VI in figure 4; figure 7 shows a partial view in section along the line VII-VII in figure 4. With reference to the drawings, we note a semi-pneumatic boat 1 comprising a semi-pneumatic hull 2, a rigid hull bottom portion 3 and two electric motors 4 with respective propulsion rotors 7. In particular we note the presence of two batteries 6 per hull to supply the two electric motors 4, located on supports 5 formed in the rigid hull bottom portion 3 to carry the batteries.

The hull 2 comprises two tubular pneumatic portions 13 in deformable inflatable material vulcanised to the rigid hull bottom portion 3, to form a single closed pressurised pneumatic chamber 100. The tubular portions 13 are for example made of rubber.

The pressurised chamber 100 encloses within it the batteries 6, resting on the supports 5, as appears clearly from figures 3 and 5.

The batteries 6 are therefore in a perfectly insulated pressurised chamber. There is no risk of said batteries 6 coming into contact with the marine environment.

The rotors 7 are located in the duct 12 formed in the rigid hull bottom portion 3.

The boat 1 has the form of a catamaran, i.e. it is constructed in such a way that the structure connecting the two hulls 2 on which the weight of the occupants bears is higher than the surface of the water, i.e. above the waterline of the boat 1, thus reducing the wetted surface area and consequently the hydrodynamic resistance, and therefore improving the boat's efficiency, reducing the disadvantages of poor performance which traditional pneumatic boats have. The boat 1 comprises furthermore a control unit 9, this too being contained in the pressurised chamber 100, connected to the batteries 6 and connected via a control cable 10 to a remote control 8 which enables the boat 1 to be controlled. The control unit 9 is also connected via motor cables 11 to the electric motors 4, so that the motors can be regulated by means of the control unit 9 and the remote control 8. - A -

The above-mentioned cable 10 runs between the pneumatically pressurised chamber and the outside environment without sealing problems because it is vulcanised at the point where it passes through the surface.

It is thus possible to eliminate the encumbrance of the outboard motor on the transom 70, and of the batteries on the boat's floorboards. The transom can therefore be made easily removable or folding, for easier embarkation and disembarkation of people and materials from land or sea. With batteries and motor no longer visible on the deck, all the space on board becomes usable for people and materials. The only "encumbrance" is represented by the remote control 8, which is anyway removable like a real key in the event that the boat is abandoned. There is no possibility of starting the motor without its remote control. The security of the boat is therefore increased.

The remote control 8 can be connected by a cable 10 to the control unit 9, or can operate wirelessly. In this case security is ensured by the need to key in an access password.

By suitably modifying the control unit 9 and with known systems for receiving and transmitting signals, it is even possible to control the boat at a distance by means of said remote control 8 in wireless mode. In the case, for example, of transporting several people, it would not be necessary to have a boatman on board to pilot the craft.

More generally, the remote control 8 can be a multi-media device, with radio and SatNav functions and also others known to those skilled in the art. Theoretically any modern cellphone or GPS device could be adapted for controlling the boat.

The batteries 6 can be connected by a recharging cable which can be connected to known charging equipment on board or on dry land.

The synchronous electric motors 4 each consist of a cylindrical propulsion rotor 7 of composite material with the permanent magnets 51 resin-bonded into it, in a watertight location, with blades 52, also made of composite material, fixed onto it. The stator 53 consists of an outer cylinder in composite material, with the electromagnets 54 resin-bonded into it in a watertight location, positioned to work with the permanent magnets in the rotor 7. The rotor 7 rotates in the stator 53 on bearings lubricated by the water itself.

There are therefore no elements for transmitting motion, such as shafts, hubs, cardan joints or inverters.

This type of propulsion unit avoids any contact between the marine environment and the electrical parts resin-bonded into the rotor and the stator, both of which are made of composite material.

This type of propulsion eliminates the need for rudders, since the boat relies for manoeuvring on the difference in speed and direction of rotation of the rotors. This gives the boat a far greater degree of manoeuvrability (it can even rotate on the spot, very useful in marinas) and intuitiveness (remote control with joystick).

With reference to the embodiment shown in figures 4-7, the boat's pneumatic chamber 100 is put under pressure (usually about 1.25 bar) by a compressor 60 connected to the control unit 9 by electric cable 65 and powered by the batteries 6. The compressor is fixed to the same support 5 as the batteries 6 and is thus also contained in the pressurised chamber 100. To pressurise the boat it is only necessary to open the sealing screw- fit plug 61 connecting the compressor 60 with the open air by means of an armoured intake tube 62, and activate the compressor by means of the remote control 8. The delivery tube 63 ensures the pressurisation of the pneumatic chamber 100 housing the batteries and the electrical equipment, which will also remain protected and sealed from the external marine environment by means of a safety valve 64.

Batteries 6, electrical equipment, motors 4 and compressor 60 are below the waterline, making the boat's centre of gravity very low. Compared with traditional inflatable tenders with outboard motors, this ensures greater stability and safety, especially when navigating in moderate seas and with a fresh breeze.

Claims

1. Electrically powered boat (1) comprising a hull (2) having at least one deformable inflatable tubular portion (13) closed and sealed by a rigid hull bottom portion (3) to form at least one closed pressurised chamber (100), at least one electric motor (4) supplied by at least one battery (6), characterised in that the battery (6) and the relative electrical equipment are located inside said closed pressurised chamber (100).

2. Boat (1) according to claim 1, characterised in that said closed pressurised chamber (100) houses an inflating compressor (60) communicating with the outside via an internal intake tube (62) which faces onto the outside by means of an outlet nozzle closed by a sealing screw-fit plug (61), and with the pressurised chamber (100) via a delivery tube (63).

3. Boat (1) according to any of the preceding claims, characterised in that the battery (6), the electrical equipment, the motor (4) and the compressor (60) are positioned below the boat's waterline.

4. Boat (1) according to claim 1, characterised by comprising a remote control (8) capable of receiving and sending signals to a control unit (9) enclosed in the pressurised chamber (100) and connected to the motor (4) for controlling the boat (1).

5. Boat (1) according to any of the preceding claims, characterised in that the normally convex rigid hull bottom portion (3) comprises at least one cavity (12) in which is housed the propulsion rotor (7) with its blades (52).

6. Boat (1) according to any of the preceding claims, characterised by having two tubular portions (13), two cavities (12) and two motors (4) electrically supplied by respective batteries (6).

7. Boat (1) according to any of the preceding claims, characterised in that the rigid hull bottom portion (3) is in composite.

8. Boat (1) according to any of the preceding claims, characterised by being a catamaran and therefore having the structure connecting the hulls above the surface of the water.

9. Boat (1) according to any of the preceding claims, characterised by comprising a demountable or folding transom for easy access to the boat (1).