EP0968915B1 - Foresail - Google Patents

Abstract

The racing spinnaker has its top fixed to the mast and bottom to a boom and a sheet. Between the upper (5) and lower (4) regions, there is at least one aperture (8) which is horizontal when the sail (3) is set. Within this aperture there is at least one lift wing (10) with aerodynamic profile, arranged so that there are through apertures above and below it for the air flowing past it. The spinnaker may be fitted to a stay and a second boom.

Description

The invention relates to a downwind sail with one on the mast attaching top area, and one to a tree and a sheet or on the stay or on a second tree or on a stay and a sheet to fasten the lower area.

Document DE 1247890 discloses such a downwind sail.

When sailing in front of the wind, the downwind sail sets, for example a spinnaker resists the airflow, causing decelerated the air flow and thereby the propulsion of the Ship is reached. The feed force that can be achieved and thus the speed of the ship is on the one hand the size of the Area of the sail and on the other hand the angle of incidence of the wind dependent on the sail. Spinnakers are said to be as much wind as possible to capture and the resulting wind or Transfer dynamic pressure over the rig to the hull of the ship. The profile of the spinnaker plays in an aerodynamic sense no or at most a very subordinate role, so that the strongest force that can be derived from the air current, namely the aerodynamic force remains unused. So that's it Application of spinnakers essentially to sailing in the Limited wind area.

Will be outside the pre-wind area, for example in the upwind area the air masses are no longer sailed decelerated, but by a flat, as aerodynamic Profile-trained sail deflected. The air mass increases the windward side of the sail (windward) is delayed and accelerated on the windward side of the sail (Lee). This creates an overpressure in the windward and in the lee through the Accelerating the air flow a significantly larger vacuum. Both forces act as a total force in the same direction, namely almost perpendicular to the direction of the incident wind. The sail therefore works on the same principle as the wing of an airplane.

The invention is based on the task of a downwind sail, especially to train a spinnaker in such a way that in addition the aerodynamic force of the air flow in addition to the dynamic pressure can be used to propel the ship forward.

According to the invention, this object is achieved with a generic Downwind sail, in particular a spinnaker solved in that between its upper and lower area at least one with the sail set in a substantially horizontal direction extending opening is provided and within the Opening at least one buoyancy part extending transversely to the sail is arranged with an aerodynamic profile such that both above and below the buoyancy part Flow opening available for the air mass flowing around this is.

Another solution to this problem can be found in a generic Downwind sail, especially a spinnaker be achieved between the top and bottom Area of the sail at least one with the sail set in substantially horizontal direction and as a flow opening is provided for the opening serving the air mass, the lower area serves as the driving part and the upper area Area formed as a buoyancy part with an aerodynamic profile whose thin end is adjacent to the opening.

In both solutions, the buoyancy element looks like a wing, the aerodynamic force of the air flowing around the buoyancy part Air mass to achieve an essentially forward and exploited upward buoyancy and thereby the mode of operation of the spinnaker is supported insofar as this relieves the hull and rig from the buoyancy become. This reduces the friction of the ship, so that this slides more easily and increases its speed this increases.

The downwind sail according to the invention represents a combination of one Buoyancy and propulsion sail, its possible use from the downwind to the half wind course.

In aft winds, this is reduced by the buoyancy part caused the hull surface of the ship to be wetted by the water. The force is transmitted from the buoyancy to the Hull preferably over two trees.

If the wind incidence angle moves more into the space or half wind area, so the advantage of the invention is increasingly in the erecting Moment of the ship, which reduces the deals and the speed is increased. In doing so, increasingly half wind then the second tree can be dispensed with if the sheet is led over a break point on deck, or if the Neck is attached to the forestay.

With the first solution, a particularly large increase in Propulsion power of the ship can be achieved in that several arranged at a vertical distance from one another and essentially openings directed parallel to one another are provided and a floating part is assigned to each of the openings.

An inexpensive solution to this arises from the fact that the upper and lower areas with bridging the opening Ribbons or lines are connected together and the buoyancy part attached to this. It is advantageous if the the tapes or lines by means of extending transversely to their longitudinal direction other bands are connected.

The same benefits can also be achieved if the upper and lower area by means of an opening bridging network are interconnected and the buoyancy part attached to this.

To achieve the aerodynamic profile of the buoyancy parts can be a hollow body, which is preferably divided into chambers are formed and each have an inlet opening for the Have air mass. This is the case with a corresponding cut of the buoyancy part whose aerodynamic profile through the Air flow or the resulting excess pressure in the chambers each one automatically.

The buoyancy parts can also be designed as closed hollow bodies and can be filled with a gas, preferably with air.

To the relative position of the buoyancy part to the sail at the wind incidence angle To make it adjustable, lines are provided that one end at the free end of the buoyancy part and at the other end on Se-gel can be attached.

Further advantages and details of the invention result from the following description of shown in the drawings Embodiments.

Fig. 1 a:

Eine Prinzipdarstellung einer ersten Ausführungsform der Erfindung;

Fig. 1 b:

Eine Prinzipdarstellung einer zweiten Ausführungsform der Erfindung ;

Fig. 1 c:

Eine Prinzipdarstellung einer dritten Ausführungsform der Erfindung ;

Fig. 2:

Eine schaubildliche Darstellung der ersten Ausführführungsform der Erfindung in Backbord-Blickrichtung;

Fig. 3:

Eine schaubildliche Darstellung der zweiten Ausführführungsform der Erfindung in Backbord-Blickrichtung;

Fig. 4:

Eine schaubildliche Darstellung der ersten Ausführführungsform in Ansicht von Achtern;

It shows:

Fig. 1 a:

A schematic representation of a first embodiment of the invention;

Fig. 1 b:

A schematic representation of a second embodiment of the invention;

1 c:

A schematic diagram of a third embodiment of the invention;

Fig. 2:

A perspective view of the first embodiment of the invention in port view;

Fig. 3:

A perspective view of the second embodiment of the invention in port view;

Fig. 4:

A diagrammatic representation of the first embodiment in aft view;

In the drawing, the hull of a (indicated) ship is 1 referred to, on which in a manner known per se for inclusion a sail serving mast 2 is attached.

In the first embodiment of the invention according to FIG. 1a, 2 and 4 has the sail 3, for example as a spinnaker is formed, a lower region 4 and an upper region 5 on. The lower area 4 of the spinnaker is by means of a Tree 6, to which a tree repeater is assigned, on mast 2 and attached to a sheet 7 on the hull 1. The sheet 7 can can also be replaced by a second boom attached to mast 2 is. The upper area 5 of the sail 3 is known per se Attached to mast 2.

Both areas 4 and 5 of the sail 3 act as a propulsion part. An opening 8 is provided between the two regions 4, 5 almost to the side of the two areas 4,5 extends and serves as a flow opening for the air mass. Both areas 4, 5 span the opening 8 Bands 9 connected together. Instead of the tapes 9 can also serve a network spanning the opening 8.

Within the opening 8, a buoyancy part 10 is provided, which as Hollow body and be divided into several chambers can. The buoyancy part 10 can be open at its sail-side end or be locked here. If the buoyancy part 10 is open is inflated by the wind; is the buoyancy part 10 as closed hollow body, so it is with a valve provided to fill it with air or another gas can. The cutting of the buoyancy part 10, which consists of a for Sails usually used material is so chosen that the buoyancy part in its active state has an aerodynamic profile. The size of this profile is dimensioned in relation to the size of the opening 8 so that the Air mass the buoyancy part 10 both on its underside and also flows around on its top, making it wing-like acts.

This will increase the aerodynamic force of the lift part flowing air mass to achieve a substantially forward and upward buoyancy exploited and supports the mode of operation of the spinnaker insofar as this relieves the hull and rig from the buoyancy become. This reduces the friction of the ship, so that this slides more easily and increases its speed this increases.

Because the size of the aerodynamic force depends on the flow conditions of the buoyancy part 10 and thus from the angle of incidence Air mass depends, is the position of the buoyancy part 10 and thus its relative position to the sail 3 adjustable by lines 11. This are at one end on the buoyancy part 10 and at the other end on the sail 3 attached, their effective length extended accordingly or can be shortened.

Structure and operation of those shown in Figs. 1b and 3 second embodiment of the invention correspond to that described above Structure and operation of the first embodiment the same.

The only difference is that here two buoyancy parts 10 are spaced one above the other. The opening is 8th chosen so large that the air mass both buoyancy parts 10 each to flow around both on their top and bottom can. Of course, it is also possible to use two accordingly to arrange smaller openings 8 at a distance from one another. It is only important that the air mass both buoyancy parts 10th both on their respective top and bottom can flow around To the position of both buoyancy parts 10 relative easy to adapt to the angle of incidence of the air mass, are the free ends of the buoyancy parts 10 by means of lines 12 connected to each other so that the position of both buoyancy parts 10 by extending or shortening the effective length of the lines 11 can be changed at the same time.

The third embodiment of the invention shown in FIG. 1c also works in accordance with the two previously described embodiments.
Here the buoyancy part 10 is not formed by a part additionally attached to the actual sail 3. Rather, the upper area 5 of the sail 3 itself is designed as a buoyancy part 10 and, like the respective buoyancy part 10 of the other two embodiments, also has an aerodynamic profile, around which the air mass flows on both its top and bottom sides. this also flows through an opening 8.

Claims (9)

1. Headwind sail, having an upper region to be secured to the mast and a lower region to be secured to a boom and a sheet, or to the stay, or to a second boom, or to a stay and a sheet, at least one opening (8) being provided between the lower and upper regions (4 and 5 respectively) and extending in a substantially horizontal direction when the sail (3) is set, characterised in that at least one raising part (10), extending transversely relative to the sail (3) and having an aerodynamic profile, is disposed within the opening (8) in such a manner that, both above and beneath the raising part (10), a throughflow aperture for the air mass flowing around said raising part is provided.
2. Headwind sail, having an upper region to be secured to the mast and a lower region to be secured to a boom and a sheet, or to the stay, or to a second boom, or to a stay and a sheet, at least one opening (8) being provided between the lower and upper regions (4 and 5 respectively), which opening extends in a substantially horizontal direction when the sail is set and serves as a throughflow aperture for the air mass, characterised in that the lower region (4) serves as the advancing part, and the upper region (5) is provided as the raising part (10) with an aerodynamic profile, the thin end of which is adjacent to the opening (8).
3. Headwind sail according to claim 1, characterised in that a plurality of openings (8) are provided, which are disposed at a vertical spacing from one another and orientated substantially parallel to one another, and a raising part (10) is associated with each of the openings (8).
4. Headwind sail according to one or more of the preceding claims, characterised in that the lower and upper regions (4 and 5 respectively) are interconnected by strips (9) which bridge the opening (8), and the raising part (10) is secured to said strips.
5. Headwind sail according to one or more of the preceding claims, characterised in that the strips (9) are interconnected by means of additional strips which extend transversely relative to their longitudinal direction.
6. Headwind sail according to one or more of the preceding claims, characterised in that the lower and upper regions (4 and 5 respectively) are interconnected by means of a net which bridges the opening (8), and the raising part (10) is secured to said net.
7. Headwind sail according to one or more of the preceding claims, characterised in that the raising parts (10) are in the form of hollow bodies and each have an inlet opening for the air mass.
8. Headwind sail according to one or more of the preceding claims, characterised in that the raising parts (10) are in the form of closed hollow bodies and can be filled with gas, preferably with air.
9. Headwind sail according to one or more of the preceding claims, characterised in that the position of the raising part (10) relative to the sail (3) can be adjusted by ropes (11), which are securable at one end to the free end of the raising part (10) and at the other end to the sail (3).

Images