WO1993008075A1

WO1993008075A1 - Propelling/steering system suitable for use on watercrafts

Info

Publication number: WO1993008075A1
Application number: PCT/IT1992/000129
Authority: WO
Inventors: Lucio Potocnik
Original assignee: Valkov, Anastas
Priority date: 1991-10-23
Filing date: 1992-10-22
Publication date: 1993-04-29
Also published as: IT1253953B; ITTS910010A1; ITTS910010A0; AU2902292A

Abstract

Propelling/steering system suitable for use on watercrafts in general, that includes the following components: a rotor (2) [improved upon what was described and claimed in the previous invention by the same Applicant, deposited in Italy on April 5th, 1989, Record, No. 82803 A/89], which is housed in an appropriate recess (3) (whose shape is similar to that of the rotor (2)) made inside the hull, near the stern of the craft (1) and transversal to its sheer plan; two (right and left) engines (12) and the related reverse-reduction units (13); a stator group (16) (right and left); and a fore-and-aft channel made on the bottom.

Description

PROPELLING/STEERING SYSTEM SUITABLE FOR USE ON

WATERCRAFTS

This propelling/steering system can be effectively used in the ship-building sector. Its use is most appropriate on fast vessels, pleasure- crafts or merchant crafts. Its peculiar propelling/steering system allows transport costs to be reduced even on large-sized ships. This system is based on an improvement on the previous invention of the same depositor-inventor; his invention was described in the application for Patent deposited in Italy on April 5th, 1989 (Record No. 82803 A/89) . Therefore, this system is a development - supported by the results of the technological tests and experiments in tank - of the original system, whose main features partly remain the same even though they have been enhanced. The abstract of the text concerning the original system is hereinafter reproduced, in order to corroborate the correlation between the new system and the original one: "Propelling system suitable for use on watercrafts; it mainly consists of a forward rotor, a set of channels made on the bottom, and secondary propelling and manoeuvring devices, that allow the craft to reach high speeds. The main rotor is located at the craft's bow, is transversal to the sheer plan, and consists of two or more sets of cylindrical wheels, which are equipped with blades. Each set of cylindrical wheels is provided with its own independent braking device.

Longitudinal channels are made on the bottom; they have different cross-sections along the sheer plan. To be more precise, their cross-sections decrease from bow and stern to the bottom centre.

Its secondary propelling and manoeuvring devices consist of rotors, water-jets or similar, components; they are located in pairs of two (or more)".

It is deemed advisable to recall here the technological objectives that led to the design and completion of both the system envisaged by the

Italian application for Patent No. 82803 A/89 and this new system.

The use of propellers for crafts' propulsion is widespread in the ship-building sector, although water-jets are recommended - especially for high speeds.

In particular, the propeller's efficiency is not very high, due to disturbance, cavitation and vibration of the bottom, wave motion and the air dissolved into water.

It should be recalled that the propeller is the propelling system most sensitive to cavitation. However, the water-jet is also subject to this phenomenon.

As everyone knows, cavitation causes an early wear and tear of the propelling system and also triggers off vibrations that could spread to the whole structure of the hull (and dramatically increase at high speeds) . The helm is a primary device for the craft's steering and causes a braking effect.

It is well-known that both the propeller and helm cause a great waste of energy - which is proportional to speed - during navigation. For instance, the use of the helm in each sheer causes increasing cavitation and braking, thus resulting in an increase in fuel consumption in order to keep the ship's speed constant - not to mention that even the fastenings of the propeller and helm cause a waste of energy due to their frictional resistance during navigation. •

The goal of this invention is to provide users with a propelling/steering system that would allow crafts to overcome the well-known failures which are typical of other propelling systems (propeller and vater-jet) , and to reach high speeds by exploiting its design potential to its utmost.

The rotor is the main component of this invention. As everyone knows, the rotor is a tangential-flow hydraulic machine, where the operative flow does not undergo any pressure variation due to the movement of the rotating components (i.e. blades) . These are called "acting machines", since their reaction degree amounts to zero (contrary to that of the propeller and water-jet) .

It follows that these machines, equipped with rotors, undergo neither cavitation nor its direct consequence, i.e. vibration.

This system mainly includes a rotor (improved upon what was described and claimed in the above-mentioned application for Patent recorded under No. 82803 A/89) , which is housed in a recess inside the hull, near the stern and with its axis of symmetry transversal to the sheer plan of the craft; a stator group, which is located on the horizontal (or inclined) plane behind the rotor (aft) ; one or more fore-and-aft channels made on the bottom and below the stator group. In particular, the rotor consists of two sets (right and left) of cylindrical wheels, w^τhich are transversal to the sheer plan of the watercraft. Each set of cylindrical wheels - which are placed side by side and supported by a horizontal shaft - is driven by a power unit by means of a coupler.

The cylindrical wheels of each set have different diameters (decreasing from the sheer plan of the watercraft to each external side) ; each wheel consists of two disks (either one or both are removable) , a hub and a crown.

The external surface of this crown supports a set of blades specifically shaped to hit water properly during immersion and permit the watercraft's heading.

The external shape of each cylindrical wheel is suited to the transversal inclination of the craft's bottom.

This shape of the wheels and hull allows each wheel (that works in parallel with the others) to fund -- at its best (peak efficiency) , since it undergoes _-.•:• variation in the speed and direction of the incoming flow.

The conditions for peak efficiency (optimization) are achieved by changing the number of r.p. . of each wheel, by means of a train of crown wheels or gearings

- each located inside the wheel and given a different gear ratio.

An engine with a suitable power drives a reverse- reduction unit, which in turn drives the most external cylindrical wheel by means of a device of angular transmission (crown-pinion) ; the motion is then transmitted from the most external cylindrical wheel to the nearest one - and so on as far as the last wheel with the largest diameter.

The rotor is therefore actuated by two (right and left) engines, each one equipped with a reverse- reduction unit.

Each reverse-reduction unit transmits the motion to its own set of cylindrical wheels.

A dividing cross member between the two sets of cylindrical wheels is located vertically in the lower part of the hull, along the sheer plan; it works as a keel dividing and steering the transversal flow created by each set.

Each hydraulic reverse-reduction unit does as follows: - it allows the motion of the kinematic chain of each set of cylindrical wheels to be turned on or off and reversed (for instance, by means of opposed rotations) , on load, thus altering the course without using the helm; it allows users to steer by actuating the other reverse-reduction unit in a proper and combined way; during this manoeuvre, the number of r.p.m. of each engine can also be changed, thus allowing for a range of continuous (manual/automatic) adjustment of course. The stator group behind each set of cylindrical wheels consists of one or more fixed blades, which have a suitable shape and are located on a horizontal or inclined plane (or planes) .

This stator group allows the outgoing flow from the blades of each cylindrical wheel to be straightened (in the axial direction) , thus recovering a part of the outgoing energy and exploiting it as a propulsive thrust.

Each fore-and-aft channel (made on the bottom and below the stator group's plane) has a variable cross- section along the sheer plan; to be more precise, its cross-section near the rotor is wider than in the central part of the hull and it widens again towards the craft's stern, where it has an inclined shape. Each fore-and-aft channel conveys the water coming from the rotor and thrusts it towards the craft's stern at a higher speed, thus benefiting from the Venturi effect.

Therefore, this procedure contributes to water conveyance with a remarkable recovery of the propulsive thrust, and reduces roll and pitch (at the craft's stern) thanks to the stabilizing effect of the flow pressure on the channel's sides. The contribution given by the stator group and fore- and-aft channels allows each cylindrical wheel to work at its best (peak efficiency) ; therefore, it allows the propulsive efficiency of the whole rotor to be more successful than that of propellers and water-jets even in a wide range of speeds.

Further characteristics and advantages of this invention will be highlighted by the attached drawings regarding a preferable - yet not exclusive realization of this propelling/steering system suitable for use on watercrafts as a non-restrictive example, wher :

Figure 1 includes a vertical section along the plane of symmetry of a watercraft equipped with the above- mentioned propelling system, and shows the rotor, stator group and fore-and-aft channel; Figure 2 includes a horizontal section along section A-A, and shows the rotor with the two related reverse- reduction units, the dividing cross member (located vertically along the sheer plan) and the fixed blades of the stator group;

Figure 3 includes a horizontal section along sections B-A, and shows the rotor with the two related reverse- reduction units, the dividing cross member and the channels on the bottom; Figure 4 shows the cross-section C-C of the craft's stern;

Figure 5 shows the cross-section D-D between the stern and the rotor; Figure 6 shows a detailed - yet partial - view of the rotor, with its own horizontal section (with the recommended type of blade) ;

Figure 7 shows a sketch of the front view of two cylindrical wheels (the recommended type of blade is highlighted) ; and

Figure 8 includes a section of five cylindrical wheels along the rotation axis, and shows the internal kinematic motions and the connection with a reverse- reduction unit. This propelling/steering system suitable for use on watercrafts (1) mainly consists of a rotor (2) housed in an appropriate recess (3) , which is made inside the hull and near the stern and whose shape is similar to that of the rotor (2) . This rotor (2) consists of two sets of cylindrical wheels (4) , splined onto two coaxial shafts (5) (right and left), which are transversal to the hull. Each set of cylindrical wheels (4) includes five cylindrical wheels (4.1, 4.2, 4.3, 4.4 and 4.5), as shown in Figures 6 and 8; each cylindrical wheel consists of two disks (6) (either one or both of them are removable) , a hub (7) and a crown (8) , whose external surface supports a set of blades (9) ; these blades are specifically designed and shaped to hit water properly during immersion and, therefore, to receive the thrust which is necessary for the watercraft's heading (1) .

The cylindrical wheels (4) of each set have different diameters (from each other) - moving from the craft's plane of symmetry (1) to the sides.

The special feature of each cylindrical wheel is to have its own shape (external diameter) fitted in the bottom (10) of the watercraft (1) (which has the same shape and a larger diameter) . Actually, the shape of the recess (3) - where the rotor C2) is housed - is similar to the external shape of the rotor (2) ; however, this recess (3) is clearly larger.

The identical inclination of the lower part of the hull and the rotor (2) implies that each wheel (4.1, 4.2, 4.3, 4.4 and 4.5) functions a its best (peak efficiency) , since it undergoes no variation in the speed and direction of the incoming and outgoing flow. The above-mentioned conditions for peak efficiency (optimization) are achieved by changing the number of r.p.m. of each wheel (4), by means of a train of crown wheels (11) (or gearings) - each located inside the wheel and given a different gear ratio. The principle of construction and functioning is essentially similar to the one thoroughly described in the above-mentioned Italian application for Patent deposited under Record No. 82803 A/89. The most important variation is that the effect of the motive power is directly applied on the two (right and left) external wheels (4.1) of each set - whose diameter is smaller (than that of the other wheels) . From these wheels the motive power - together with the consequent rotary motion - is subsequently passed on to the other wheels (4.2, 4.3, 4.4 and 4.5). On the other hand, in the original patent, the effect of the motive power was applied on the two (right and left) central wheels (4.1) of each set (whose diameter was larger than that of the other wheels) and was then passed on to the other peripheral wheels (4) . The transmission diagram of each set of cylindrical wheels (4) is implemented as follows: the engine (12) drives the reverse-reduction unit (13) it is connected with; in turn this unit (13) drives a cylindrical wheel (4.1) by means of a device of angular transmission (14). The motion is then transmitted from this cylindrical wheel (4.1) to the nearest one (4.2), and so on as far as the last wheel (4.5) with the largest diameter. A vertical dividing cross member (15) is located between the two sets of cylindrical wheels (4) along the sheer plan.

This dividing cross member (15) works as an effective keel dividing and steering the transversal flow created by each set of cylindrical wheels (4) and as a fore-and-aft support of the hull.

The stator group (16) consists of two (right and left) fixed blades (16.1) and (right and left) ducts (16.2); it is located behind the rotor (2) . The fixed blades (16»1) are located on a slightly inclined plane. This stator group (16 _») allows the outgoing flow from the rotating blades (9) of each set of cylindrical wheels (4) to be straightened (in the axial direction) , thus recovering a part of the outgoing energy and exploiting it as a propulsive thrust. The (right and left) fore-and-aft channels are made on the bottom (10) and below the stator group (16) . Each of them has a variable cross-section along the sheer plan; this cross-section is larger near the rotor (2) , smaller in the central part of the hull, whereas it widens again towards the craft's stern (1), thus benefiting from the Venturi effect as already stated. The thrust is ensured by the indipendent action of each set of cylindrical wheels (4) . Therefore, each set (4) may have either the same number of r.p.m. as the other or a different one; this is possible for both the ahead and astern movements. The course of the craft (1) can be held and/or changed without using the helm. If necessary, one set of cylindrical wheels (4) can be rotated in a given direction and the other set (4) in the opposite one.

The craft's hull (1) may have any bottom shape or external shape with regard to the level of draft and its use, provided that it is equipped with a recess (3) towards the stern. This invention, as it stands, may undergo several modifications and/or variations, all within the invention's concepts as described above; moreover, all its components may be replaced with others which are technically equivalent.

Claims

CLAIMS 1 - PROPELLING/STEERING SYSTEM SUITABLE FOR USE ON ATERCRAFTS, characterized by the following components: a rotor (2) , housed in an appropriate recess (3) , which is located inside the hull and near the craft's stern (1) , and whose shape is similar to that of the rotor (2) ;

- two (right and left) engines (12) ; - two reverse-reduction units (13) ;

- a stator group (right and left) , that consists of a fixed blade (16.1) and one or more ducts (16.2); one or more fore-and-aft channels (17) made on the hull's bottom. 2 - PROPELLING/STEERING SYSTEM SUITABLE FOR USE OX WATERCRAFTS, according to Claim 1 above, which is characterized by a main rotor (2) , consisting of two independent sets of cylindrical wheels (4) , splined onto two (right and left) coaxial shafts (5) , which are transversal to the hull; by each set of cylindrical wheels (4) , which includes several cylindrical wheels (4.1, 4.2, 4.3, etc.), each consisting of two disks (6) (either one or both of them are removable) , a hub (7) and a crown (8) whose external surface supports a set of blades (9) with a functional shape; by the cylindrical wheels (4) of each set, which have different diameters (from each other) - moving from the craft's plane of symmetry (1) to the sides; and by a vertical dividing cross member (15) , located between the two sets of cylindrical wheels (4) along the sheer plan.

3 - PROPELLING/STEERING SYSTEM SUITABLE FOR USE ON WATERCRAFTS, according to Claims 1 and 2 above and the statements in the application for Patent No. 82803 deposited in Italy on April 5th, 1989, which is characterized by a train of crown wheels (11) , each located inside a wheel (4) and given a different gear ratio.

4 - PROPELLING/STEERING SYSTEM SUITABLE FOR USE ON WATERCRAFTS, according to the Claims above, which is characterized by two (right and left) engines (12) with a suitable power; these engines (the one independent of the other) drive the reverse-reduction units (13) by means of a device of angular transmission (14) , which in turn drives each most external cylindrical wheel (4) (whose diameter is smaller than that of the other wheels) ; the motion is then transmitted from this cylindrical wheel (4.1) to the nearest one (4.2), and so on as far as the last wheel (4.5) with the largest diameter. 5 - PROPELLING/STEERING SYSTEM SUITABLE FOR USE ON WATERCRAFTS, according to the Claims above, which is characterized by the shape of the recess (3) containing the rotor (2) : its shape is suited to the outline of each wheel (4) of the rotor (2) .

6 - PROPELLING/STEERING SYSTEM SUITABLE FOR USE ON WATERCRAFTS, according to the Claims above, which is characterized by a stator group (16) including one or more properly-shaped fixed blades (16.1) - located on one or more planes behind each set of cylindrical wheels (4) - and a duct (16.2).

7 - PROPELLING/STEERING SYSTEM SUITABLE FOR USE ON WATERCRAFTS, according to Claim 1 above, which is characterized by one or rather two (right and left) fore-and-aft channels (17) made on the bottom of the hull below the stator group (16), in the area between the rotor (2) and the craft's stern. Each of these fore-and-aft channels (17) has a variable cross- section along the sheer plan; this cross-section is larger near the rotor (2) , smaller in the central part of the hull, whereas it widens again towards the craft's stern (1).

8 - PROPELLING/STEERING SYSTEM SUITABLE FOR USE ON WATERCRAFTS, according to the Claims above, where the main thrust is ensured by the independent action of each set of cylindrical wheels (4) ; therefore, . each set (4) may have either the same number of r.p.m. as the other or a different one (during both the ahead and astern movements). The course of the craft (1) can be held and/or changed without using the helm. If necessary, one set of cylindrical wheels (4) can be rotated in a given direction and the other set (4) in the opposite one. 9 - PROPELLING/STEERING SYSTEM SUITABLE FOR USE ON WATERCRAFTS, according to the Claims above, where each wheel (4.1, 4.2, 4.3, 4.4 and 4.5) (of both right and left sets (4) ) functions at its best (peak efficiency) , and the aggregate flow resulting from the blades (9) is tangential to the jet ducts (16.2) formed by the stator group (16) and the fore-and-aft channel (17) .