FR2658477A1 - Retractible boat keel - Google Patents

Abstract

The invention relates to a keel composed of two half-keels (1 and 2) back to back, opening laterally so that they move aside and become a horizontal support. Each half-keel is articulated at the upper part (3 and 4). A force (5 and 6) actuates them separately and as desired, from the vertical position to the horizontal position. The method is intended to allow sailing boats to dock in very shallow waters. By the lateral displacement of a half-keel with its ballast (7 or 8) into the "return, into the wind" position, the invention also favours the increase in sail area, and therefore speed.

Description

DESCRIPTION
retractable boat keel
The present invention relates to a boat keel composed of two vertical retractable parts, joined, opening laterally to disappear and become a horizontal support. This process favors docking on shores in very low water.

 This result is already partially obtained by the principle of the "guillotine" keel, rising entirely and vertically inside the boat. In addition to the drawback of the drift well cluttering the center of the best habitable part of the boat, this traditional system does not keep the boat horizontal while beaching, which then turns out to be particularly uncomfortable.

 The keel proposed according to the invention makes it possible, inter alia, to remedy these drawbacks.

It is, in short, composed according to the basic principle of Figures 1 and 2, two vertical half-pins (1 and 2), articulated in the upper part (3 and 4) and which, under the impulse of one or several cylinders
and hydraulics (5 and 6) open laterally to fade away horizontally under the boat.

 These half-pins (1 and 2) can be made of simple sheets of steel, stainless steel or other material. They are cut and composed according to the shape, the curve and the profile defined by the naval architect. The thickness as well as the additional thicknesses possibly added in the upper part are sufficient to support the weight of the boat during docking.

 For the same reason, the fixing of the articulations (3 and 4) and the anchor points of the jacks (5 and 6) will be particularly studied and reinforced. To avoid water entry and clutter in the boat, this mechanism contains under the floor which forms the waterproofing box.

It is possible to multiply the number of "hinges" of joints (3 and 4) on the same half-keel (Figure 8) which allows
- to shorten the deflection levers (9 and 10), therefore to lower the level of the floor.

 - to better distribute the forces on the half-pins and on the boat's infrastructures.

 The return levers (9 and 10) form an angle or have curves so that the half-pins (1 and 2) press against each other in a vertical position and against the shell in a horizontal position.

 Figure 6 gives an example of articulation on a steel or plastic shell. To simplify the drawing, only the movement of a half-keel is shown.

 FIG. 7 represents what could be the adaptation of the method according to the invention on a wooden boat, even an old one. In order to avoid turbulence, the crossing of the hull by the half-pins must be curved and the articulation offset so that the opening in the hull is reduced to a minimum.

 The jacks (5 and 6) can be arranged differently than in the example of FIGS. 6 and 7, in the search for the compromise between efficiency, size and transmission of forces.

 In the present case, the jacks and therefore the half-pins are controlled separately by distributors according to any current hydraulic installation. An energy accumulator, such as "nitrogen pressure" can be incorporated in the oil pressure circuit in order to allow the maneuvers of the half-pins with the on-board engine stopped.

 The cylinders (5 and 6) can be replaced by any other usual system such as a worm, rack, hauling, etc.

 The position of the half-pins under the boat is transmitted to the interior via a usual process such as a sheathed cable. I1 is connected on the one hand to the top of the levers (9 and 10) and activates at the other end a "reduced model" on the dashboard.

 Each half-keel (1 and 2) is provided with a ballast (7 and 8) in its lower part. It is a mass of heavy material, more or less traditionally profiled according to criteria of economy of manufacture and yield, or in the form of fins very elaborate for competition.

 FIG. 1 represents the basic position, that which is adopted for the so-called normal cruise. The two half-pins are completely joined and form a similar set of appearance and behavior to a common type keel.

 Figure 2 shows the two half-pins raised horizontally.

The boat is grounded, stable, in shallow water.

 Figure 3 describes the important phase of approach and docking on a shore: the two half-pins are raised to three-quarters.

During contact with the strike, by the simultaneous action of the half-pins, the boat is slightly raised and leveled, immobilized despite the shelling. The installation of an anchor is then, in principle, unnecessary.

This position of the half-pins raised to three-quarters also allows the advance "groping" on a doubtful bottom. In the event of unfortunate grounding, the escape is then always possible by the maneuver represented in the following figure.

 Indeed, Figure 4 shows schematically the afloat or the stranding: the half-pins are simply raised completely against the hull and the boat floats again.

 Figure 5 shows the position of the half pins for road transport. The reduced height of the boat allows movement on normal trucks or semi-trailers. The use of a cradle, even on land is useless.

 Figure 8 - This is the longitudinal view of a boat with an example of a keel according to the invention. All other forms are possible, whatever the material of the boat: plastic, steel, aluminum, wood, etc ... We can clearly see the joints (3 and 4).

------ The present process, in addition to the advantage of docking in low water, allows, by moving a ballast (7 or 8) to the position of "recall, to the wind", a significant increase in the airfoil, therefore the speed.

Figure 9 illustrates this function
the half-keel "downwind" (2) remains vertical, ensuring the "drift";
the half-keel "in the wind" (1) is raised as far as possible against the hull. By the effect of the deposit, its ballast (7) is then located out of water.

It is no longer reduced by the "Archimedes push" and regains its full weight in the most favorable "recall" position.

 This result is currently obtained, in competition, by pumping water into special tanks, called ballast and placed in the boat, "windward" side. It has the disadvantage of weighing down the boat with this liquid mass, causing additional depression and therefore a reduction in speed. This ballast system also prevents the boat from righting when capsizing in a storm. The present invention easily remedies this drawback by automating the rapid return to the "normal keel", then controlled by the lying position of the boat.

------ In the variant (Figure 11) which increases this principle of "recall" the two weights 7 and 8 are replaced by a single block (11) capable of forming a body, with the choice, with one or the other half bowling (1 or 2).

The locking is effected by means of hydraulic cylinders acting as bolts, in the large profiled strikes, cast in one block with the ballast (11). This method of attachment can be replaced by any other usual system such as large screws driven by hydraulic motor, hooks, etc.

 Safety contacts prohibit unlocking on one side if the latches on the other half-keel are not engaged.

 FIG. 11 illustrates the application of this variant which improves the advantages of FIG. 9: the boat behaves like a dinghy with the whole ballast located out of water, at the "call to the wind".

The half-keel (2) which has become a single fin, without ballast, can be placed, for better performance, either in the axis of the boat as in Figure 9, or vertically (Figure 11). Without its ballast, it offers less resistance than an entire normal keel, with its two fins.

 An accentuation of the "ballast recall" can also be brought about by the extension of the "windward" half-keel and, if necessary, of the vertical half-keel acting as a drift. This process is shown diagrammatically in dotted lines in FIG. 11. Each half-keel is then lined with another half-keel sliding like a drawer. The operation is ensured by a conventional but space-saving system such as a threaded rod, its "nut" and a hydraulic motor or a simple long cylinder.

 It is obvious that this sophisticated and delicate equipment to maneuver is, in principle, intended for competition boats.

------- A second variant is shown diagrammatically in FIGS. 12 and 13.

 It retains the basic half-pins (1 and 2) but the weights are replaced by two undercarriages (13) called tracks, of common construction but insensitive to corrosion due to sea water. guidance are traditionally provided by a hydraulic motor housed in each track.

 Their section is reduced to the maximum for better penetration into the water in the "cruising" position (figure 12), but flattened for sufficient lift on the shore sand (fig. 13).

 In order to reconcile and realize these two positions, an angle (14) is formed at the bottom of the two half-pins. It is more or less open depending on the width of the boat, the length of the half-pins and the desired clearance in the position of displacement on land.

 This variant allows the boat to climb on its own on land or to return to the open sea despite a low tide (Figure 13).

------- This principle can obviously be applied to motor boats, without a keel.

 The joints are then very far apart so that the very short half-keels, with their tracks, fold completely into the bottom of the boat in the navigation position. The half-pins have, of course, a curve ensuring the shape of the closed hull.

 The rolling position on the ground becomes similar to that of FIG. 13, but with the joints more apart and the half-pins very shortened.

Claims (9)

------- 1) Retractable boat keel, opening in two, laterally, to disappear and become a horizontal support, (Figures 1 and 2) process characterized in that it is, in fact, composed of two adjoining half-pins (1 and 2) articulated (3 and 4) and actuated (5 and 6) in the upper part.  2) Device according to claim 1, characterized in that the upper part of the half-pins (1 and 2), and the levers (9 and 10), are curved or form one or more angles (FIGS. 6 and 7) allowing, whatever the infrastructure of the boat, to pass from the side-vertical position to the position placed under the boat.  3) Device according to claim 1, characterized in that a ballast (7 and 8), equips the bottom of each half-keel (1 and 2).  4) Device according to claims 1 and 2 characterized in that an existing process such as a sheathed cable permanently transmits the position of each half-keel in the boat. ------- 5) Device according to claims 1 and 2, characterized in that the bottom of the half-pins (1 and 2) is provided with a single ballast (11) and a locking system ( Figure 10) allowing this ballast to be secured independently of one or the other of the half-pins (fig. 11).  6) Device according to claim 5 characterized in that the locking system (Figure 10) is provided with safety contacts prohibiting unlocking on one side if the locks of the opposite half-keel are not engaged.  7) Device according to claims 5 and 6 characterized in that each half-keel is extendable, at will (Figure 11), by means of a traditional sliding system (12). ------- 8) Device according to claims 1 and 2 characterized in that the bottom of each half-keel (1 and 2) is provided with a self-propelled undercarriage (13) called "track" (Figures 12 and 13).  9) Device according to claim 8 characterized in that the lower part of the half-pins (1 and 2) forms an angle (14) which ensures the clearance between the tracks in the "rolling" position on the ground and retains the joining of the two half-pins in vertical position for navigation.