FR2502579A1 - Wing for para-glider construction - has material folded back on itself at load attachment points to provide reinforcement to hollow aerofoil - Google Patents

Abstract

The paraglider has a hollow construction with an upper panel and lower panel interconnected by vertical partitions which define channels for the flow of air from the leading edge to the trailing edge. Supports for carrying loads are fixed at or near the point of intersection between the lower part and certain vertical partitions the material being folded back on itself at these points for reinforcement.

Description

Soft wing
The invention relates to a flexible wing comprising a box type airfoil, comprising an upper surface, a lower surface and vertical walls, called ribs, defining channels for the flow of air, which extend from an edge d attack towards a trailing edge, lines being fixed on or at the lower surface, in line with certain ribs, for securing a load.

 Generally, in this type of parachute, provision is made at the level of the attachment of the lines to the lower surface of the wing of the means of stress distribution, in order to transfer the tension of the lines to points on the upper surface located between its edges. of attack and flight.

 These stress distribution means can for example be constituted by several reinforcing tapes or bands fixed on the ribs by means of seams and extending so as to diverge from each other from the attachment points of the lines, in direction of the upper surface.

 Such an embodiment has been described in particular in French patent No. 70 37672 filed on October 19, 1970 by SNYDER.

 Provision can also be made, in order to distribute the tensile forces of the lines equally, to have wedge-shaped parts at right angles to the ribs, which are connected by their lower points to the lines.

Such an embodiment has been described in particular in French patent No. 1,526,922 filed on 11.11.66 by SPACE RECOVERY
RESEARCH CENTER.

 All these devices ensuring the distribution of stresses complicate the structure of the wing and increase the cost price; moreover, in certain cases, they can harm its aerodynamic qualities.

 The present invention overcomes these drawbacks.

It relates to a flexible wing comprising a box-type wing comprising an upper surface, a lower surface and vertical walls, called ribs, defining channels for the flow of air which extend from one edge d 'attack towards a trailing edge, lines being fixed on or in the vicinity of the lower surface to the right of certain ribs for securing a load, characterized in that at least the ribs to the right of which are fixed the lines are provided with folds
According to one embodiment, the folds are located in the vicinity of the lower surface and extend parallel to eelui-ei.

 According to another embodiment, the folds extend substantially perpendicular to 1 lower surface and affect the rib over its entire height from the lower surface to the upper surface.

 According to another embodiment, the ribs may include folds located in the vicinity of the lower surface and extending parallel thereto, as well as folds extending substantially perpendicular to the lower surface and affecting the rib over its entire height, from the lower surface to the upper surface.

 The folds can be held by pinching at their ends and or by sewing at the folds.

Other characteristics of the invention will emerge from the description which follows and from the appended drawing in which
Figure 1 shows sehémac: Equement a plan view of a rib of a flexible wing according to i invention.

 Figure 2 is a section along line 1-6ne A-A of Figure 1.

 FIG. 3 is a variant of FIG. 1.

 Figure 4 is a section along line B-B of Figure 3.

 FIG. 7 represents a rib I connecting the upper surfaces to the lower surface of a flexible wing and deflecting, in combination with these elements and another rib, a channel for the flow of air.

 The rib can be formed by a nylon cover for example.

 Reference 2 designates attachment means for fixing the lines.

 In certain areas, identified by the reference 3 and located to the right of the attachment means 2, in accordance with the invention, the rib 1 is folded back on itself, so as to form extra thicknesses, as is clearly shown in FIG. 2 .

 In the case of Figures 1 and 2, the reinforcing folds thus created are substantially vertical and they affect the rib 1 over its entire height, from the lower surface to the upper surface, the junction line of the rib to the lower surface being referenced 4 and the junction to the upper surface being referenced 5.

 In FIG. 2, a double fold has been shown, but one could obviously envisage a quadruple fold, in particular in the vicinity of the leading edge.

 FIGS. 3 and 4 relate to a variant of the embodiment shown in FIGS. 1 and 2.

 In this case, the rib has been reinforced in a zone 6 extending parallel to the junction line 4 with the lower surface by a fold parallel to this line 4; in Figure 4, there is shown a double fold, but one could consider a quadruple fold.

 These folds can be maintained by sewing at the folds thus formed, but it is also possible, in particular in the embodiment shown in Figures 1 and 2, to hold them by pinching at their ends.

 It is also possible to provide embodiments associating substantially vertical folds and a fold extending parallel to the lower surface.

 The size of the folds and their number on a rib can be variable depending on the desired resistance.

 Furthermore, in the case of substantially vertical folds, the angle of the folds with respect to the junction line of the rib with the lower surface may be variable depending on the position of the fold with respect to the leading edge and the edge leak.

 We can also plan to develop from a single point several folds extending between the lower surface and the upper surface at different angles, that is to say diverging.

 Compared to previously known devices, the present invention makes it possible to increase the resistance to the stresses caused by the action of the load on the lines without introducing into the flexible wing an additional element, the fixing of which can be delicate and which causes a increase in cost price. In the context of the invention, it suffices to provide a slight increase in the surface of the material which constitutes the rib.

 Of course, the invention is in no way limited to the embodiments described and shown which have been given only by way of examples.

Claims (5)

1 / Flexible wing comprising a box type wing comprising an upper surface, a lower surface and vertical walls, called ribs, defining channels for the flow of air which extend from a leading edge in direction d '' a trailing edge, lines being fixed on or near the lower surface in line with certain ribs for securing a load, characterized in that at least the ribs (1) to the right of which are fixed the lines are fitted with folds. 2 / flexible wing according to claim 1, characterized in that the folds are located in an area (6) in the vicinity of the lower surface and extend parallel thereto. 3 / flexible wing according to one of claims 1 and 2, characterized in that folds extend in zones (3) substantially perpendicular to the lower surface and affect the rib (1) over its entire height of the lower surface to upper surface. 4 / flexible wing according to one of the preceding claims, characterized in that the folds are held by pinching at their ends. 5 / flexible wing according to one of the preceding claims, characterized in that the folds are maintained by sewing at the folds.