FR2670003A1 - An instrument for aiding sailing navigation - Google Patents

Abstract

The invention relates to an instrument allowing recreational sailors to determine immediately whether or not they can follow the route which they decided, considering the direction of the wind, and - if so, to know the attitude (trim) and the setting corresponding to the advance of the boat, - if not, to know the minimum port and starboard tack heading to get to the destination. It consists of a fixed part and two moving parts, freely fastened concentrically at the centre of a compass dial carrying, in addition to a degree division, the four cardinal and intermediate points, the rotations of which make it possible to take the aforementioned readings. Although particularly intended for pleasure sailing, this instrument may also have use in teaching.

Description

 The present invention relates to a navigation aid instrument for sailing.

 The movements of pleasure craft using the force of the wind to move are subject to the weather conditions present in the navigation area (direction and force of the wind).

 The use of this propulsion mode is surrounded by a certain number of constraints including that linked in particular to the impossibility for the boat to be able to progress facing the wind, and moreover supposes its own prior technical knowledge, relating to the specific adjustments of the sails, according to the gaits.

 The instrument according to the invention allows boaters who prepare their navigation to make the most of the current weather conditions even when their technical knowledge is still only imperfect or insufficient.

 The user, after having traced "his route" by means of a traditional rule, and positioned the instrument according to the instructions, is able to immediately determine whether it is possible for him to follow the route that he set himself, - if so, to know the correlative setting of the sails for the adopted pace, - if not: what are the "port" and "starboard" tack to hold to allow him to get to destination by avoiding placing the boat in the sector facing the wind, preventing any progress.

 FIG. 1 represents, seen from above, the fixed part of the instrument according to the invention.

 FIG. 2 represents, seen from above, the first mobile part of the circular type instrument.

 FIG. 3 represents, seen from above, the second movable part of the instrument diagramming a boat.

With reference to its drawings: - the fixed part of the instrument (FIG.1) supports engraved:
-on its left side, a compass rose divided into degrees, and comprising the four cardinal and subcardinal points (1),
-on its right-hand side, a graph (2) making it possible to visualize water height curves as a function of the wind force by reference to the Beaufort scale of wind speeds in knots,
-on the entire surface with the exception of the aforementioned areas, a locating grid (3).

- the movable circular part (FIG.2) of the instrument supports engraved:
-a drawing symbolizing a boat seen from above, reproduced identically for each of the main gaits of progression of a boat with vélique propulsion (4),
-for each of these gaits, the preceding symbols are supplemented by the pictogram of the corresponding setting of the sails (opening, position) (5), or of faseyage (6) for the boat located in the "upright" sector, hatched (7 ) in which the word "WIND" is found,
- the name of the main aforementioned progression gaits (8).

 This part includes a hatched sector protruding by 900 between the two words "PRES" mentioned on either side of the word "WIND".

This sector which represents the zone in which a boat driven by the wind cannot normally progress can be reduced to a lower value within the limit of 750 according to variants not illustrated.

 Finally, this sector includes, above the word "WIND", a zone fitted out as a window (9) intended to come to overlap, and allow the reading of the cardinal and intermediate points located on the compass rose.

-the movable part (FIG.3) supports engraved:
- a drawing symbolizing a boat, seen from above, comprising at its finest end, an arrow which is positioned by rotation opposite the divisions in degrees of the compass rose to allow reading.

 The three parts are obtained from a screen printing process, or any other type of hot or cold etching, of translucent films of PVC, plastic or similar type, of sufficient thickness to give satisfactory rigidity to the material. 'together.

 When the user has traced the route to follow on the map, he places the center of the compass rose on the starting point, then: - oriented the instrument so as to match the "North" of the instrument with the North of the nautical chart, using the grid provided for this purpose, - brings the word "WIND" appearing on the circular mobile part (FIG.2) opposite the wind direction announced for the area (North, South-East, ect.) The latter appearing in the window, - rotates the mobile part symbolizing the boat (FIG.3) to direct the point in the direction of the road towards the point of destination.

He then appears; - either that the road does not enter the hatched "headwind"sector; in which case, the instrument makes it possible to immediately determine by simple reading:
-the gait of the boat,
-the correlative setting of the sails,
-the true heading and the compass heading, for verification, and possible correction of the drift.

- or that the road is in the "headwind" sector: in this case, the instrument allows the user to realize that it will be necessary to use the engine or pull the edges to get to the destination . In this hypothesis, the instrument indicates, opposite the ends of the hatched protruding sector; what are the minimum true headings to adopt to maintain the gaits "closer", port and starboard tack.

 These indications can be transformed into compass caps by the user who will be able to trigger his most appropriate tack transfers to the caps.

 The instrument according to the invention is intended for pleasure boating, which is not incompatible with use for educational purposes.

Claims (4)

 1- Instrument for aid to navigation under sail, characterized in that it comprises three translucent parts, one of which is fixed and two mobile (FIG. 2 and 3) assembled freely in the center of a compass rose (FIG. 1) graduated in degrees and comprising the four cardinal points and the intermediate points.  2- Instrument according to claim 1 characterized in that the rotation of the movable part (FIG.2) to bring the window appearing above the word "WIND" (6), followed by that of the movable part (FIG.3) to bring the center line of the boat in the direction of the route to be followed allows the user to know immediately if the fixed route can be followed, and failing this what are the true minimum port and starboard tack lines to be held by the coxswain for get to your destination by "pulling edges" and avoid the "headwind" sector.  3- Instrument according to claim let2 characterized in that the longitudinal graduation of the mobile part (FIG.3) allows by the effect of its superposition on the mobile part (FIG.2), and by transparency, the reading of the pace of progression and the correlative setting of the sails which it is necessary to carry out to go in the chosen direction.  4- Instrument according to the preceding claims characterized in that the reading of the heading indicated opposite the end of the movable part (FIG.3) allows to proceed to the correction of the drift of the boat related to the influence of the wind.