WO2024023789A1

WO2024023789A1 - Watercraft

Info

Publication number: WO2024023789A1
Application number: PCT/IB2023/057699
Authority: WO
Inventors: Pawel Wawrzynski
Original assignee: Pawel Wawrzynski
Priority date: 2022-07-29
Filing date: 2023-07-28
Publication date: 2024-02-01
Also published as: PL441878A1

Abstract

The vessel is provided with a mast (4), a boom (5) attached rotatably with respect to the mast (4), and a triangular sail (S) fixed to the mast (4) and boom (5). The boom (5) is attached to the mast (4) rotatably at a fixed tilting angle, with a mechanism for rotating the boom (5) around the mast (4), advantageously in the form of sheets. The sail (S) is fixed with its top (B) to the top of the mast (4), while the tack point (A) of the sail (S) is fixed pointwise to the yard arm of the boom (5), while to the clew point (C) of the sail (S) sheets (6) are attached, which are hooked on the other side to the hull (H) of the vessel at two points (8L, 8R) located between the stern of the vessel and the mast (4).

Description

Watercraft

The object of the invention is a watercraft, specifically a vessel with a mast and a sail used as main or auxiliary propulsion, intended for navigation specifically on inland waters and seas.

A design of a sailboat fitted with a mast to which a boom is attached rotatably, and the position of the boom is adjustable by means of a sheet, is commonly known. A triangular sail is attached to the boom and mast.

From the description of PL195837, a sailing rig of a watercraft is known, fitted with two inverted V-shaped masts and a boom rotatably mounted to a bracket and furthermore attached with its ends through stays to the top of the masts. In the event of a risk of capsizing, letting go of the sheet brings the sail into line with the wind regardless of the position of the hull of the vessel in relation to the wind direction.

From the description of WO 86/ 07325, a sailing vessel with two outboard hulls and at least one sail is known. Each sail is set on a matching stay attached to the forward end of a boom or spreader, the rear end of which is supported by another stay. Each sail may be raised or lowered along the stay or furled around the stay. Each boom is attached to the watercraft to allow rotation about an axis extending adjacent to the luff of the respective sail.

Additionally, a sailing vessel comprising a mast and a sail is known from GB1389989, which has an upper part mounted rotatably on the mast and a lower end attached to a first boom mounted rotatably between its opposite ends so that the sail can rotate about an axis passing through the mast. The first boom is mounted in a rotating layout to the second boom at one end while the opposite end of the second boom is mounted rotatbly to the lower end of the mast.

In known designs, the sails are fully or mostly on the leeward side of the vessel’s plane of symmetry. The resultant force on such sails always acts in such a way that it pushes the vessel forward and tilts it to the leeward side. Two exceptions to this rule occur when the wind is blowing from behind the vessel or from the front.

From the Polish patent description PL 202346, a sailing device is known for non-tilting propulsion of vessels, especially racing yachts, sport yachts, tourist yachts, passenger and cargo water transport vessels and sledges with special skids with lateral resistance planes. The device consists of a boom, attached to the main hull rotatably, supported by a transverse girder on the auxiliary hulls, and a propulsion surface positioned thereon. This surface is tilted so that the force of the wind passes at the height of the lateral resistance of the main hull so that the tilting moment caused by the wind is completely balanced. The device ensures that even very large propulsion surfaces can be used safely. The aim of the invention is to construct a watercraft with a rig that does not tilt the craft in crosswinds and contains a small number of components.

The invention is a watercraft having a mast, a boom mounted so that it swivels relative to the mast and a triangular sail with sheets fixed to the mast and boom. The essence of the invention is that the boom is attached to the mast rotatably at a fixed tilting angle, with a mechanism for rotating the boom around the mast, while the sail is attached with its top to the top of the mast. The tack point of the sail is fixed pointwise to the yard arm of the boom, whereas sheets are attached to the clew point of the sail, which on the other side are attached to the hull of the vessel at two points situated between the stem of the vessel and the mast.

Preferrably, the yard arm of the boom is connected to the top of the mast by a topping lift to which the edge of the sail is attached.

In such a case, it is preferred for the topping lift to have the form of a rigid strand. In a further preferred embodiment, the rotating mechanism of the boom is in the form of sheets hooked to the hull of the vessel at two points located on different sides of the vessel longitudinal axis passing through the mast.

In such an embodiment, it is preferred for the sheets passing through the attachment points to be tensioned by the engines.

In another preferred embodiment, the vessel is fitted with an additional boom sheet attachment point on the hull, located on or above the plane defined by the attachment points and the sheet to boom fixing point, between the mast and the bow of the vessel. In this design, it is also preferred that the sheets passing through the attachment points are tensioned by the engines.

The solution according to the invention, in contrast to known types of rigging, allows the sail to be set safely to the windward side. The sail works on the windward side of the vessel, it is tilted forward and to leeward. As a result of this positioning of the sail, the resultant wind force acting on it is directed forward and down the vessel, instead of forward and to the leeward side as in other types of watercraft. Thus, the sail in the solution according to the invention does not tilt the vessel, instead it pushes it down into the water, i.e. acts as ballast. The new solution has a positive effect on the safety and comfort of watercraft, especially sailboats. In addition, the solution can also be used in large mechanically propelled vessels as an additional propulsion system, which will increase their sailing speed and reduce fuel consumption, while maintaining the proper position of the vessel, without additional tilting that may result from the effect of wind on the sail.

The invention is illustrated in more detail in the exemplary embodiments in the following description and in the accompanying drawing presenting schematically on fig. 1 the watercraft with a sail which conceals items which would be invisible from the right perspective, while the same side of the sail is visible from each perspective, fig. 2 - the watercraft from fig. 1 with visible structural components, fig. 3 — the watercraft with marked resultant force acting on the sail upon a horizontal plane, a plane perpendicular to the fore-aft axis of the watercraft and on its plane of symmetry, fig. 4 - adjustment of the sail setting to the wind direction, fig. 5 - turn taking by the watercraft, fig. 6 - the watercraft in another simplified exemplary embodiment.

In the figure, reference 1 indicates the top view of the vessel, reference 2 indicates the rear view of the vessel and reference 3 indicates the left view of the vessel.

The vessel comprises a vertical mast 4 and a boom 5 diverging from it, horizontal or tilted downwards. Preferably, the boom 5 is fixed rotatably with respect to the mast 4, and is always tilted towards the mast at a fixed angle. The boom 5 is fitted with a mechanism for rotating the boom 5 about the mast 4, for example in the form of sheets 7L, 7R hooked to the hull H of the vessel at two points 9L, 9R, located on different sides of the vessel longitudinal axis passing through the mast 4. The sheets 7L, 7R in the form of a rope control the position of the boom 5. The sail S is attached with its top B to the top of the mast 4. The tack point A of the sail S is fixed pointwise to the yard arm of the boom 5, while sheets 6L, 6R are attached to the clew point C of the sail S and these are hooked on the other side to the hull H of the watercraft at two points 8L, 8R situated between the stem of the watercraft and the mast 4.

In a preferred embodiment, the yard arm of the boom 5 is connected to the top of the mast 4 by a topping lift 45, to which the AB edge of the sail S is then attached. The topping lift 45 is advantageously in the form of a rigid strand, for example a beam or tube, but can also be in the form of a rope. The vessel may optionally be fitted with an additional attachment point 10 of the sheets 7L, 7R of the boom 5 on the hull H. The attachment point 10 is located on or above the plane defined by the attachment points 9L, 9R and the attachment point of the sheets 7L, 7R to the boom 5, between the mast 4 and the bow of the vessel. This location of the attachment point 10 facilitates control of the position of the boom 5. The attachment point 10 may be in the form of a rod on which the sheet 7L or 7R rests. The rod may be either fixed, with a sliding surface for the 7L, 7R sheets, or rotating, for example a capstan, with possible additional safeguard to prevent the sheets falling out.

Advantageously, the 6L, 6R and 7L, 7R sheets are tensioned by engines, which, however, is not shown in the drawing for clarity reasons.

The 8L, 8R, 9L, 9R attachment points can be in the form of a capstan or chain pipe.

In the watercraft according to the invention, the sail S is exposed to the windward side. The sail S works tilted forward and to leeward. As a result of this positioning of the sail S, the resultant wind force F acting on it is directed forward and downwind of the vessel, as shown in detail in fig. 3. As a consequence, the sail S does not tilt the vessel sideways, but instead pushes it down into the water, i.e. it acts as ballast.

For the sail S to work effectively, it is essential that it is properly positioned toward the wind. It should be positioned in such a way that the vector CA determined by the lower edge of the sail S is directed between the vector determining the direction of movement of the vessel and the vector indicating from which side the wind is blowing, as shown in fig. 4. To achieve this, clew C should be tensioned on the left side of the vessel by sheet 6L or on the right side by sheet 6R. In addition, the boom 5 should be set at the correct angle with respect to the fore-aft axis of the vessel. The 7L and 7R sheets are used for this purpose. To ensure easy setting up of any angle, sheets 7L and 7R connect boom 5 to hull H on their left and right sides, and depending on the position of boom 5, this means connecting these ropes to attachment points 9L, 9R or 9L, 10 or 10, 9R. The change from one configuration of the attachment points to another occurs automatically when the boom 5 moves from one side of the attachment point 10 to the other. Such a change occurs automatically when the attachment point 10 is on or above the plane defined by the attachment points 9L, 9R and the point of attachment of the sheets 7L, 7R to the boom 5.

Fig. 5 illustrates the turning of the vessel: from upwind to downwind: sheeting of ropes 6R and 7R with slackening of sheets 6L and 7L; from upwind to downwind from the right (right tack): further sheeting of ropes 6R and 7R while slackening the sheets 6L and 7L; from upwind from the right to downwind: sheeting the rope 7L, slackening the sheet 7R; from downwind to downwind from the left sheeting the rope 6L and 7L while slackening the sheet 7R.

Fig. 6 presents a simplified example of the design of a vessel without an additional attachment point 10. List of references on the drawing:

H — hull of the ship

S - sail

W — wind

F — resultant wind force acting on the vessel

A — tack point of the sail

B — top of sail

C — clew point of sail

1 - view from above

2 - rear view

3 - view from left

4 - mast

5 - boom

45 — topping lift

6L, 6R — left and right sail sheet S

7L, 7R — left and right boom sheet 5

8L, 8R — left and right attachment points for sheets 6L, 6R to the hull;

9L/R — left and right attachment points for sheets 7L, 7R to the hull;

10 — additional attachment point

Claims

1. A watercraft, provided with a mast, attached rotatably with respect to the boom, and a triangular sail with sheets fixed to the mast and boom, characterised in that the boom (5) is attached rotatably to the mast (4) at a fixed angle of inclination, with a mechanism for rotating the boom (5) around the mast (4), the sail (S) is fixed with its top (B) to the top of the mast (4), the tack point (A) of the sail

(5) is fixed pointwise to the yard arm of the boom (5), and sheets

(6) are attached to the clew point (Q of the sail (S), which sheets (6) are hooked on the other side to the hull (H) of the vessel at two points (8L, 8R) located between the stem of the vessel and the mast (4).

2. The vessel according to claim 1, characterised in that the yard arm of the boom (5) is connected to the top of the mast (4) by a topping lift (45), to which the sail edge (S) is attached.

3. The vessel according to claim 2, characterised in that the topping lift (45) is in the form of a rigid strand.

4. A watercraft according to any one of claims 1-3, characterised in that the boom rotating mechanism (5) is in the form of sheets (7) hooked to the hull (H) of the watercraft at two points (9L, 9R) located on different sides of the watercraft longitudinal axis passing through the mast (4).

5. The vessel according to one of the claims 4, characterised in that the sheets (7) passing through the attachment points (9L, 9R) are tensioned by the engines.

6. The vessel according to claims. 4 or 5, characterised in that it is equipped with an additional attachment point (10) for the sheet (7) of the boom (5) on the hull (H), located at or above the plane determined by the attachment points (9L, 9R) and the attachment point of the sheet (7) to the boom (5), between the mast (4) and the bow of the vessel.

7. The vessel according to claim. 1, characterised in that the sheets (6) passing through the attachment points (8L, 8R) are tensioned by the engines.