WO1995001906A1

WO1995001906A1 - Single-hull craft with high floating stability

Info

Publication number: WO1995001906A1
Application number: PCT/EP1994/002183
Authority: WO
Inventors: Mamilio Pivot; Adriano Dondi
Original assignee: Mamilio Pivot; Adriano Dondi
Priority date: 1993-07-07
Filing date: 1994-07-04
Publication date: 1995-01-19
Also published as: ITTO930500A0; IT1261088B; AU7187394A; ITTO930500A1

Abstract

A single-hull craft with high floating stability, having one hull (11). This single-hull craft comprises means of steering and stabilizing the craft in the water, including a combined keel and rudder (18) pivoting about an axis, which are connected to means (15, 14, 17, 17.1, 16.1, 16.2, 30, 31) of controlling the direction and trim of the said craft, and which, if the craft lists, are operated to laterally displace a body of water in the direction of the list, with a consequent counter-reaction of the hull (11) which therefore returns to the correct trim in the water.

Description

SINGLE-HULL CRAFT WITH HIGH FLOATING STABILITY

The present invention relates to a single-hull craft with high floating stability.

The term "single-hull craft" is used here to designate a means of locomotion on expanses of water (lakes, rivers, sea, etc.) for various uses, but particularly for the purposes of amusement, recreation and sport. Examples of such single-hull crafts are surfboards, canoes, etc., which are light, easily transportable, fast and easily manoeuvrable in the water. The principal object of the present invention is to provide a single-hull craft as specified, which offers a person simple and safe control of its floating stability, ensuring, in particular, the dynamic equilibrium of the craft.

A further object is that of providing a single-hull craft as indicated which, while comprising effective means of propulsion and stabilizing, is of simplified structure, light, inexpensive and highly attractive because of its versatility in application.

Given these objects, the present invention provides a single- hull craft with high floating stability, whose essential charac- teristic forms the subject of the principal claim, which is to be understood as being included here in full.

Further advantageous characteristics will be understood from the subordinate claims which are also to be understood as being included here in full. The present invention is described in detail below with reference to the attached drawing, provided solely by way of example, in which

Fig. 1 is a schematic side elevation of a single-hull craft with high floating stability according to the present invention; - Fig. 2 is a detail view, on a larger scale and in longitudinal section, of the craft shown in Fig. 1;

Fig. 3 is a view similar to that in Fig. 2, but shows a variant embodiment of the craft according to the present invention;

Fig. 4 is a sectional view through the line IV-IV in Fig. 3. With reference to Figures 1 and 2 initially, the number 10 (Fig. 1) indicates the whole of the single-hull craft with high floating stability according to the present invention.

The said single-hull craft 10 comprises, by way of example, a floating surfboard, forming the hull 11 of the craft. The number 12 indicates the whole of a propulsion, steering and stabilizing unit for the craft, mounted on the hull 11, using for example the fastenings and sockets for the installation of the keel in a floating surfboard. The said propulsion, steering and stabilizing unit 12 comprises base means in the form of a plate 13 fixed to the hull 11 and forming a pedestal 13.1 on the upper face of the board.

A supporting and covering case 13.2 is fixed at the front of the pedestal 13.1 and a supporting bracket 13.3 is fixed at the rear.

In the case 13.2, a first metal tube 14 is mounted so that it is freely rotatable on a pair of bearings 14.1 about an axis lying in the longitudinal vertical median plane of the hull 11 and inclined with its upper end towards the bow of the hull. Handlebars 15 are connected and fixed by a screw clamp 15.1 to the upper part of the said metal tube 14 which extends up above the case 13.2, while a first spur gear 16.1 with external teeth is keyed coaxially to the lower end of the metal tube.

A second metal tube 17 is held so that it is freely rotatable with respect to the base wall of the case 13.2 and extends below the hull 11, through a hole 11.1 provided in the hull, with an axis parallel to that of the first metal tube 14 and lying in the said longitudinal vertical median plane of the hull 11. A second cylindrical gear 16.2 with external teeth corresponding to those of the gear 16.1 is keyed coaxially to the upper end of the second tube 17, inside the case 13.2, and engages with the said first gear 16.1.

At its end beneath the hull 11, the second metal tube 17 carries a metal tubular supporting arm 17.1, fixed to it, for example by welding, substantially in a flattened "L" shape and with a free branch 17.2 pointing towards the hull 11. The axes of the branches of the said arm 17.1 are substantially coplanar with the axis of the second metal tube 17.

A combined rudder and keel in plate form 18 is supported so that it can oscillate about a pivot 18.1 with a horizontal axis, fixed in the free end area of the branch 17.2 of the supporting arm 17.1.

A driving shaft 19 is fitted with its upper coaxial and freely rotatable part through the upper part of the second metal tube 17, and has a first bevel gear 19.1 with external teeth keyed to its upper end and held by a supporting plate so that it is freely rotatable in the case 13.2. The lower part of the driving shaft 19, disposed at an angle to the upper part, passes out through a wide slot in the second metal tube 17 under the hull 11. For this purpose, the said driving shaft 19 is hinged by an intermediate universal joint 19.2 and a universal joint 19.3 near the end remote from the first bevel gear 19.1.

A screw 20 is fitted so that it rotates integrally with the driving shaft 19 at the said end remote from the first bevel gear 19.1, in which the shaft is held by bearing means (not visible in the drawing) and by a vertical supporting plate 17.3, fixed for example by welding between the second metal tube 17 and the arm 17.1. The βcrew 20 is located in front of the combined rudder and keel 18 with respect to the direction of advance of the craft. A pedal unit 21, with two pedal cranks 21.1 and corresponding pedals 21.2, is supported on the case 13.2 by a shaft 21.3, rotatable on bearings about a horizontal axis (see also Fig. 4) . A second bevel gear 21.4 with external teeth corresponding to those of the first bevel gear 19.1, but of greater diameter, is keyed to the said shaft 21.3 and engages with the said first bevel gear 19.1.

A saddle 22 is supported in a telescopically adjustable manner by means of a cylindrical metal tubular support 22.1, fixed to the supporting bracket 13.3, with its axis lying in the said longi- tudinal vertical median plane of the hull 11 and inclined with an upward divergence from the first metal tube 14 which supports the handlebars.

A link 23 connects the said tubular support 22.1 to the case 13.2. With this disposition, a user sits on the saddle 22 and pedals with the pedal unit 21 as in a conventional bicycle. This drives the screw 20 which propels the craft 10. The user holds the ends of the handlebars 15, again as in a conventional bicycle.

During the floating of the craft 10, if balance is lost, with a tendency to fall to one side, the user instinctively rotates the handlebars 15 about the axis of the first metal tube 14 towards the direction of the sideways fall. This rotation is transmitted to the second tube 17 carrying the combined rudder and keel 18, through the pair of gears 16.1, 16.2 engaged with each other, and consequently a clockwise rotation of the handlebars 15 about the axis of the first metal tube 14 is converted into an anti-clock¬ wise rotation of the combined rudder and keel 18 about the axis of the second metal tube 17 and vice versa. The rotation of the combined rudder and keel 18 in the direction opposite that of the handlebars 15 enables the state of dynamic equilibrium of the craft 10 to be immediately re-established. There is a lateral displacement of a body of water in the same direction as the list, with a consequent counter-reaction of the hull 11 which therefore returns to the correct trim. Moreover, while moving the combined keel and rudder 18 with the handlebars 15 the user can continue to pedal, imparting a propulsive force to the craft 10. The screw 20 incorporated in the propulsion, steering and stabilizing unit 12 acts in a directional way with the combined keel and rudder, thus increasing the stabilizing effect.

It will be noted that the steering effect of the combined keel and rudder 18 also makes the craft 10 more stable in its advance in the water and makes it possible to turn with adjustable inclinations even on waves. This makes it possible, in the application to surfboards for example, to freely select whether to remove or leave in place the rear steering fin in order to increase the manoeuvrability of the means of transport to a greater or lesser degree.

In the variant illustrated in Figures 3 and 4, parts similar to those shown in Figures 1 and 2 are indicated with the same reference numbers and are not described further.

In the present variant, the combined keel and rudder 18 is connected directly to the handlebars 15 by means of a metal tube 30 and a substantially U-shaped tubular supporting arm 31 fixed to the lower end of the said metal tube, which is submerged when in use. The connection between the metal tube 30 and the supporting arm 31 is made by detachable connecting means 30.1. The metal tube 30 is supported so that it is freely rotatable in the case 13.2 on a pair of bearings 14.1. The handlebars 15 are fixed at the upper end, outside the case 13.2, of the said metal tube 30, while the metal tube extends beneath the hull 11 through a hole 11.1 provided in the hull. The supporting arm 31 has axes of its branches coplanar with that of the said metal tube 30.

Additionally, the hinged driving shaft 19 is replaced here by a flexible driving shaft 32 disposed so that it passes through a corresponding hole 33 in the hull 11.

For the rest, reference should be made to the description provided above with reference to Figures 1 and 2.

In this case, a rotation of the handlebars 15 about the axis of the metal tube 30 always corresponds to a rotation in the same direction of the combined keel and rudder 18 about the same axis. The user is therefore required to have a greater ability to control the craft 10, since for recovery from a sideways list of the craft he must rotate the handlebars 15 in a direction opposite that of the list, which is contrary to instinct.

The combined keel and rudder 18, mounted so that it oscillates about the pivot with a horizontal axis 18.1, permits navigation even in shallow water, in which the combined keel and rudder, on touching the bottom, is made to pivot upwards without becoming grounded, while it is returned by gravity to the original position when it is clear of the bottom.

Naturally, numerous variations may be made in practice to what has been described and illustrated purely by way of example and without restriction, without departure from the scope of the invention and consequently from the domain of the present patent.

For example, the present invention is also applicable to crafts of the type known as "pedalos" , in other words those with means of propulsion consisting of a paddle wheel in place of the screw.

Additionally, the combined keel and rudder may be supported in such a way that it can pivot directly on the hull.

Furthermore, means of transmission of the motion different from those illustrated and described purely by way of example may be used.

Motor means may also be applied to the craft according to the invention, to impart a motive power to the driving shaft.

Obviously, the propulsion, steering and stabilizing unit of the craft according to the invention may also be applied to existing hulls such as conventional surfboards and the like.

It should be noted that the handlebars may be replaced by a tiller or other lever member for controlling the combined keel and rudder.

Claims

1. Single-hull craft with high floating stability, having one hull (11) , characterized in that it comprises means of steering and stabilizing the craft in the water, including a combined keel and rudder (18) pivoting about an axis, which are connected to means (15, 14, 17, 17.1, 16.1, 16.2, 30, 31) of controlling the direction and trim of the said craft, and which, if the craft lists, are operated to laterally displace a body of water in the direction of the list, with a consequent counter-reaction of the hull (11) which therefore returns to the correct trim in the water.

2. Craft according to Claim 1, characterized in that the said control means comprise steering members (15, 14, 16.1, 16.2, 17, 17.1, 30, 31) controlled by the user of the craft to determine the direction and trim of the craft, and in that the said steering members include a steering bar (15) held by the user and rotating about an axis and members (14, 16.1, 16.2, 17, 17.1, 30, 31) for transmitting the rotation of the said steering bar (15) to the said combined keel and rudder (18) .

3. Craft according to Claim 2, characterized in that the said transmission members (14, 16.1, 16.2, 17, 17.1, 30, 31) transmit the rotation imparted by the said steering bar (15) to the said combined keel and rudder (18) in directions of rotation opposite to each other, so that, if the craft lists, and if the user is instinctively induced to rotate the said steering bar (15) towards the direction of the list, the opposite rotation imparted to the combined keel and rudder (18) enables the trim of the craft to be brought back into balance.

4. Craft according to Claim 1, characterized in that it comprises a propulsion, steering and stabilizing unit (12) including the said means of steering and stabilizing and control (18, 15, 14, 16.1, 16.2, 17, 17.1, 30, 31) and means of propulsion (21, 19, 32, 20) , which act in a directional way with the said combined keel and rudder (18) , increasing the stabilizing effect and permitting, for example, turning manoeuvres with adjustable inclinations even in waves.

5. Craft according to Claim 4, characterized in that the said means of propulsion include a pedal unit (21) , and means of trans¬ mission of the motion (19, 32, 19.1, 21.4) from the said pedal unit to a screw (20) , which is supported integrally and in front of the said combined keel and rudder (18) with respect to the direction of advance of the craft.

6. Craft according to Claim 5, comprising saddle means (22) which enable the user to pedal in a seated position, as on a bicycle or a pedalo for example, characterized in that the said steering bar (15) consists of handlebars which can be operated in the same way as bicycle handlebars.

7. Craft according to Claim 5, characterized in that the said means of transmission of the motion comprise a driving shaft (19,

33) .

8. Craft according to Claim 1, characterized in that the said combined keel and rudder (18) is supported so that it can pivot about a horizontal axis (18.1) in a way which permits navigation even in shallow water, in which the combined keel and rudder, on touching the bottom, is made to pivot upwards, without becoming grounded, while it is returned by gravity to the original position when clear of the bottom.