This invention relates to a wind propulsion unit particularly for life floats.

Floats of the most varied forms are known for use for various purposes in water, and part cularly for rescue and pleasure purposes. They generally consist of an annular body of circular, elliptical, square or rectangular plan and circular or polygonal cross-section- If the interior of the annular body is not provided with a bottom the float is known as a ring or lifebelt, whereas if provided with a bottom the float is known as a raft .

The material with which the body is constructed can be of various types, and in particular rubber, rubberized fabric or flexible plastic for inflatable floats, or expanded plastic for rigid floats. Independently of their form, the presence or absence of a bottom, their construction material or their application, known floats are able to perform only one function, namely that of supporting one or more persons resting on them or gripping a cord applied to them, and in no way are they able to be moved along the water or be steered in any movements generated by the current, other than in terms of a purely minimum contribution by the arms of the persons supported by

them.

An object of the invention is to obviate this drawback by proposing a wind propulsion unit applicable to any float to convert it into an actual sailing boat. A further object of the invention is to propose a wind propulsion unit which when applied to the float combines all the sail and rudder controls within o~e region easily accessible to a single person-

A further object of the invention is to propose a wind propulsion unit which does not require permanent modi ications or alterations to be made to the float, which can be restored to its original configuration at any time-

A further object of the invention is to propose a wind propulsion unit which is of simple construction and low cost, 5 and able to be easily used by inexpert persons.

A further object of the invention is to provide a wind propulsion unit of sectional type, ie formed from several parts which when in the unassembled state occupy a very small space and form an accessory with which for example inflatable o ^or self-inflatable life rafts can be equipped.

These and further objects which w ll be apparent from the description given hereinafter are attained according to the invention by a wind propulsion unit, particularly for

life floats, characterised by comprising:

- a member to be connected to at least one point on the float;

- a mast mounted on said connection member to support a sail; - a fin rigid with the connection member and extending below said float;

- a rudder hinged to the fin; and

- rudder control members applied to said connection member.

Two preferred embodiments of the present invention are described in detail hereinafter by way of non-limiting example with reference to the accompanying drawings in which:

Figure 1 is schematic perspective view of a propulsion unit according to the invention applied to an inflatable raft of circular plan; Figure 2 is a partial vertical section on the line II-II of

Figure 1 ; Figure 3 is an exploded perspective schematic view thereof but without the sail; Figure 4 is a modified embodiment of the member by which it is connected to the float ; and

Figure 5 is a schematic section view of the unit provided with an electric motor. As can be seen from the figures, the propulsion unit

according to the invention is described with reference to its application to an inflatable circular raft, comprising a toroidal element or ring 1 provided with a lower closure fabric 2 and a pair of semicircular dunnages 3 resting on said fabric 2 to stiffen the bottom. Again for this purpose the dunnages 3, which are of a size such as to be able to be inserted with their semicircular edge between the toroidal element 1 and the fabric 2, have their straight edge shaped to allow mutual insertion-fit ing, so that the overall bottom of the raft is rigid and perfectly locked in position. The propulsion unit according to the invention, to be applied to the raft as thus described, comprises basically the following essential parts, which are described in detail hereinafter in terms of their structural and functional interconnections: - a member 4 for connection to the toroidal element 1,

- a mast 5, mounted on said connection member 4 to support a sail 6,

- a fin 7, extending from the connection member 1 in a diametrical direction below the fabric 2,

- a rudder 8 hinged to the fin 7, and

- rudder control members, fitted to said connection member 4. The connection member 4, the fin 5 and the rudder θ are constructed of an expanded plastics material, which combines

the advantage of high mechanical strength with the advantages of considerable lightness and substantial inalterability with time, even under their particular conditions of use-

The connection member 4 comprises a concave portion 9 extending as an arc of a circle of radius slightly less than the radius of the cross-section of the tubular element 1 when in its inflated state.

To the concave portion 9 there is fixed a band 10 of flexible material, provided at its end with a hole 11 for engagement by a corresponding hook 12 provided on one of the two dunnages 3-

In the connec ion member 4 there is provided a cylindrical seat 13 of vertical axis for the insertion of the mast 5. This mast is preferably of the collapsible type, ie formed in several segments which can be inserted one into another, or of telescopic type.

Conventional systems are provided to ensure both that the mast retains its mounted configuration and remains fixed into its seat 13. The sail 6 is mounted over the mast 5. For this purpose the sail is provided with a sleeve 14 for said mast 5 and with conventional retention systems (not shown) to prevent its accidental escape, such as in the case of exceptional

gusts of wind.

The inclined edge of the sail 6 comprises a plurality of further sleeves 15 to receive stiffening rods .6 which keep the sail extended in the absensσe of a boom- At that vertex of the sail 6 distant from the sleeve 14 there is provided a handgrip 17 for controlling the sail.

The fin 7 extends downwards from the connection member 4 and then horizontally below the fabric 7. It is preferably constructed in several parts 7' which can be insertion-fitted together at their adjacent vertical edges. For this reason these edges have complement ry insertion profiles, which however do not extend along their entire length but terminate before the lower horizontal edge of the corresponding part 7', so that a stop is formed for their mutual sliding during the assembly of the fin.

The cross-section through the fin 7 is substantially constant and is in the form of a concave isosceles triangle, with its base facing upwards. As will be more apparent hereinafter, this enables its wider upper part to be provided with two passage channels for ropes 18 for controlling the rudder 8.

In a modified embodiment, not shown on the drawings, the bottom -of the fin 7 or its constituent parts 7' is enlarged

to define a cavity in which ballast such as water or sand can be placed to increase the weight of the bottom of the fin and thus provide increased stability to the boat in the case of lateral wind. At that end of the fin 7 distant from the connection member 4 there is provided an element for its connection to the float. In the illustrated example this connection element is a hook 19 to be engaged in a ring 20 thermowelded to the fabric 2 or to the actual toroidal element 1 , although a second connection member could be provided similar to the connection member 4 (but without the seat 13 for the mast 5) by which the fin 7 could be fixed to the toroidal element 1 in a position diametrically opposited the member 4.

In the case of. non-inflatable floats provided with a rigid bottom, the suitable shaped upper edge of the fin could be inserted into a corresponding guide groove provided in said bottom.

The rudder 8 is hinged to that vertical edge of the fin

7 distant from the connection member 4. This hinging can be implemented by conventional hinges fixed to both, or more simply by a suitable choice of constituent material for the two parts and thinning this material down at the hinge line.

The rudder 8 is fitted with a cross bar 21 to which are

fixed the ends of the ropes 18 and the ends of two springs 22 which at their other end are fixed to the fin 7 to ensure that the rudder 8 and fin 7 remain coplanar in the absence of external stresses. The rudder control members are also connected to the connection member 4. These consist of two ropes which as stated are fixed to the cross bar 21 , then extend through the corresponding channels provided in the fin 7 and in the actual connection member to emerge from this in a position facing the interior of the float. They can then be provided at their free end with any handgrip, suσhe as a ball grip, a knot or the like.

In the embodiment shown schematically in Figure 4, the rudder control members consist of a sort of handle 23 operable by the feet of a person lying in the raft, and fixed to a vertical shaft 24 connected to the cross bar 21 by a pair of tie rods.

In a modified embodiment not shown on the drawings, a conventional bar is connected to the rudder 8 for direct operation by the person in the raf - For this purpose the fin 7 is extended to the rear beyond the outline of the float 1 and a vertical shaft is fixed to the rudder to receive the control bar. In this case if is preferable for this vertical

shaft to traverse a second connection member fixed to the toroidal element 1 in a position diametrically opposite the member 4.

The procedure for assembling the device according to the invention and applying it to the raft is as follows.

The fin 7 is firstly fitted to the connection member 4, and then the rudder 8 to fitted to the fin before receiving its control ropes 18, which have previously been passed through their seats. The connection member 4 is then fixed to the tubular element before it is completely inflated. This is done by bringing the concave portion 9 of the connection member 4 into contact with the toroidal element 1 and then passing the band 10 about this latter and hooking its hole 11 over the hook 12 on the dunnage 3. The ring 20 on the fabric 2 is then passed over the hook

19 of the fin 7 and inflation of the toroidal element 1 is then completed, to rigidly secure the unit formed by the connection member 4, fin 7 and rudder 8 to the raft.

The mast 5 is then passed through the sleeve 14 in the sail 6, to which the rods 16 have already been fitted, and its lower end is then inserted into the seat 13 in the connection member 4, the raft now having been transformed into a perfectly steerable sail boat.

Instead of completely embracing the toroidal element 1 , the connection member 4 could embrace it only partly by for example being provided not with the band 10 but with elastic connectors to be hooked to rings thermowelded onto the toroidal element 1. Alternatively, especially in the case of bottomless floats, the band 10 can embrace the toroidal element 1 and then be hooked directly to the actual connection member 4 or fin 7, which in this case is preferably secured to the toroidal element 1 at two diametrically opposite points.

I dependentl of the particular embodiment and the specific arrangements which it comprises, the propulsion unit according to the invention has numerous advantages, and in particul r: - it enables an unσontrallable float to be converted into a true sailing boat, able to utilize the wind and be steered practically without any limitation, - it is of very simple and economical construction and is quick and easy to assemble, - it can be easily collapsed into elements which occupy a very small space and represent a useful accessory for use for example by inflatable life rafts so that they are no longer at the mercy of the current but can be steered in

any water, - it can be used to convert any play raft into a first sailing boat which a child can use for example in a swimming bath to learn the basic rudiments from an instructor on land-

In the embodiment shown in figure 5 the fin 7 is provided at the back with a seat 24 for an electric motor 25 driving a little screw 26 facing the rudder 8. The electric motor 25 is housed in a casing matching with the shape of the seat 24 and their mutual connection is obtained through any means suitable to ensure a good sealing, particularly snap engaging or through a threaded ring nut , or screws or 1ike.

From the seat 24 it departs a channel 27 extending along the fin 7 and the connection member 4 to come out inside the toroidal element 1, that is on a zone available to people set down inside the raft .

Inside this channel 27 there are two cables 28 connecting the electric motor 25 to a battery 29 housed inside a compartment 30 foreseen in the inner wall of the toroidal element 1 or in a seat provided in the connection member 4. The regulation of the feed can be carried out with a switch 31 or with a potenziometer, applied near the coming

out opening of the channel 27 inside the raft.

This embodiment is more advantageously since it allows to carry out the drive of the raft also in absence of wind, or however in all the cases in which the control of the sail could be difficult.