US3690603A

US3690603A - Arrangement for increasing the lift and/or sustaining power of sails, and sails including this arrangement

Info

Publication number: US3690603A
Application number: US61617A
Authority: US
Inventors: Pierre Marcel Lemoigne
Original assignee: Etudes et Fabrications Aeronautiques SA
Current assignee: Etudes et Fabrications Aeronautiques SA
Priority date: 1969-08-08
Filing date: 1970-08-06
Publication date: 1972-09-12
Anticipated expiration: 1989-09-12
Also published as: FR2055752B1; ES382924A1; IL35056A0; CA921450A; FR2055752A1; SE377788B; GB1314579A; DE2038910A1; SU361554A3

Abstract

The sail at least partially comprises pockets each presenting a generally conical, pyramidal or frusto-pyramidal form with its concavity directed towards the inner surface of the sail. A part at least of these pockets constitutes nozzles accelerating the flow of air and/or modifying the direction of the flow.

Description

United States Patent Lemoigne [54] ARRANGEMENT FOR INCREASING THE LIFT AND/OR SUSTAINING POWER OF SAILS, AND SAILS INCLUDING THIS ARRANGEMENT [72] Inventor: Pierre Marcel Lemoigne, Montrouge, France [73] Assignee: Etudes et Fabrications Aeronautiques, Paris, France [22] Filed: Aug. 6, 1970 [21] Appl. N0.: 61,617

[30] Foreign Application Priority Data Aug. 8, 1969 France ..6927330 [52] I US. Cl ..244/l45 [51] Int. Cl. ..B64d 17/18 [58] Field 01 Search ..,....244/145, 142

[56] References Cited UNITED STATES PATENTS 3,298,639 l/1967 Heinrich et a1. ..244/ 145 51 Sept. 12,1972

3,504,874 4/1970 Lemoigne ..244/ l 42 FOREIGN PATENTS OR APPLICATIONS 1,418,752 10/1965 France ..244ll45 Primary Examiner-Milton Buchler Assistant Examiner-:Carl A. Rutledge Attorney--Jacobi, Lilling & Siegel 5 7] ABSTRACT The sail at least partially comprises pockets each presenting a generally conical, pyramidal or frustopyramidal form with its concavity directed towards the inner surface of the sail. A part at least of these pockets constitutes nozzles accelerating the flow of air and/ormodifying the direction of the flow.

5 Claims, 13 Drawing Figures PATENTEDSEH 2 m2 sum 1 OF 2 ARRANGEMENT FOR Rm AND/R SlJSTlNG t :i

SAILS llNQLlJDlNG THIS t.

the sail is subjected.

The invention has as its object an arrangement for increasing the lift and/or the sustaining power of sails such as particularly those of parachutes, of airships, or of boats, characterized in that it comprises a plurality of pockets, constituting at least part of the sail, each of generally conical or pyramidal form with its concavity facing towards the inner surface of the sail, pockets of which at least part constitute nozzles accelerating the flow of air and/or modifying the direction of this flow.

, The arrangement according to the invention can advantageously comprise pockets of one or more of the following groups:

(a) normal pyramidal nozzle-pockets, each constituted by several adjacent panels each having, when flat, a generally trapezoidal shape, this pocket including an escape orifice situated at the base of one of these panels and an anti-shock opening situated in its upper P (b) elongated pyramidal nozzle-pockets, of a structure analogous to the foregoing, but with a base area which is a multiple of the base area thereof;

(c) conical nozzle-pockets, each constituted by two panels, the one of slotted triangular shape, the other of triangular shape, incurved on the former and presenting a free edge defining an escape orifice;

(d) pyramidal brake-pockets, each constituted by several adjacent panels each having, when flat, a generally trapezoidal shape, this brake-pocket having only an anti-shoclc opening situated in its upper part.

The normal pyramidal, elongated pyramidal and conical nozzle-pockets comprise in fact anti-shock nozzles, sustainers and flow accelerators, guiding and accelerating the flow of air between the inner and outer surfaces of the sail.

The brake-pockets alone constitute receptor elements for thrust and brakes for reducing the flow.

To facilitate their inclusion in the sails, the pockets preferably have square bases of the same dimensions except for the elongated pyramidal nozzle-pockets which each have a rectangular base of an area preferably twice that of the bases of the other pockets.

The remainder of the sail is preferably constituted by elements of the same base area as the pockets which facilitates the manufacture of the sail.

The choice of a square module facilitates the arrangement of pockets to obtain flow parallel to one or several predetermined directions.

The use of pockets in an arrangement according to the invention permits a simple arrangement of some relatively to others in accordance with a squared grid.

To enable the user to influence the escape of air passing through the escape orifices of the pockets which are provided, the arrangement according to the invention preferably comprises control means for varying the section of the escape orifices of at least one of these pockets.

in the case of certain applications of sails for parachutes, these means can be adjusted during folding, in such a manner that they reduce the cross-section of the escape orifice to a minimal value, this cross-section being capable of being later modified by the operator in the course of his flight.

This arrangement is particularly valuable in the case of the use of such parachutes sails for group jumps usually effected by airborne troops. In the first stage of the jump, the orifices reduced to their minimal crosssections facilitate the separation of the parachutists, while in a second stage of this jump the operation of the control means permits these orifices to be opened to the desired cross-section and thus a precision course to be followed.

Also, depending on the use to which they are to be put, parachutes according to the invention can be provided with sails:

(a) either only with normal pyramidal, elongated pyramidal and conical nozzle-pockets, in the case of competition parachutes;

(b) or with normal pyramidal, elongated pyramidal and conical nozzle-pockets together with brakepoclrets in the case of parachutes for airborne troops or commandos.

The invention extends of course to all kinds of sails, flexible as well as rigid or semi-rigid making use of the arrangement defined above.

These sails and particularly their pockets can be made in any convenient materials and in particular of natural or artificial textiles.

The assemblies of sail elements and pockets which, when made from a textile, are preferably reinforced with bands, can when made of plastic, be simply reinforced with an extra thickness of material and/or welding of the edges of the constituent panels.

in each case the design of the manufacture of the sails from triangular elements has the great advantage of avoiding any deformation of the assembly.

in the case of certain sails never submitted to abnormal shock, the elements can be assembled with fastenings rendering the provision of reinforcing bands unnecessary, which permits significant reduction in weight.

The invention will be better understood by the reading of the detailed description which follows and examination of the accompanying drawings which represent by way of non-limitative examples several embodiments of the invention.

in these drawings:

MG. 11 is a developed plan view before assembly, of textile panels from which a normal pyramidal nozzlepocket embodying the invention is made;

FlGS. 2 and 3 are respectively a perspective view and a section along a of the nozzle-pocket of FIG. 1 after assembly;

PKG. d is a developed plan view before assembly, of textile panels from which an elongated pyramidal nozale-pocket embodying the invention is formed;

v the flow terminated by an escape orifice 25 (FIG.

FIG. 5 is a section on b of the nozzle-pocket of FIG. 4 after assembly;

FIG. 6 is a developed plan view before assembly of textile panels from which a conical nozzle-pocket embodying the invention is made;

FIG. 7 is a section on c of the nozzle-pocket of FIG. 6 after assembly;

' FIG. 8 is a perspective view of a brake-pocket embodying the invention;

FIG. 9 is a section on FIG. 8;

FIG. 10 is a plan view of a parachute sail embodying the invention;

FIG. 11 is a plan view of a publicity sail embodying the invention;

FIG. 12 is a rear view, in section along e of the sail d of the brake-pocket of of FIG. 1 1 and illustrating the modification of flow controlled by the deformation of the central part of the sail;

FIG. 13 is a rear view of a side element, with a controlled volume of flow, of the sail of FIGS. 1 1 and 12.

The normal pyramidal nozzle-pocket 1 shown in FIGS 1 to 3 is constituted by four

trapezoidal panels

2, 3, 4 and 5, of which the first three are identical and the fourth is of larger size than the three others'to define, by incurvature, a sustaining and accelerating surface for the flow, 6, terminated by an escape orifice crossed by the flow of which the direction is indicated by the arrow 7. In the upper part of the nozzle-pocket l is defined an anti-shock opening 8 through which air flows as indicated by the arrow 9.

The

panels

2, 3, 4 and 5 are assembled together and with adjacent elements (not shown) of the sail, comprising the nozzIe-pocket l, by reinforcing bands 10.

The

panels

2, 3, 4 could be replaced by a single panel cut in a corresponding shape on which the bands would define the edges of the replaced panels.

The elongated pyramidal nozzle-pocket 11 shown in FIGS 4 and 5 is constituted by three

panels

12, 13 and 14 attached to the rest of the surface (not shown) by their respective edges l5, l6 and 17 and to each other by their adjacent edges, 18 with 19, 20 with 21, 22 with 23. The base 24 of panel 14 remains free and forms, the panel being incurved, a sustaining surface accelerating 5) crossed by the flow in the direction indicated by the arrow 26. Between the

panels

12 and 13 there is preferably provided an anti-shock opening27 (shown only in FIG. 5 through which the air flows as shown by the arrow 28. On

panels

13 and 14 are carried reinforcing bands 29 defining the elementary triangular panels. Like the panels which will be described, those constituting the nozzle-pocket of FIGS. 4 and 5 could equally be formed from the assembly of simple triangular panels.

The conical nozzle-pocket 30 shown in FIGS. 6 and 7 is constituted by two

panels

31 and 32 joined together by their respective edges 33-34 and 35-36, while the

sides

37, 38, 39 of panel 31 are connected to the adjacent elements (not shown) of the sail and while the edge 40 of the panel 32 remains free and forms when curved inwards on assembly, a surface accelerating the flow terminated in an anti-shock escape orifice 41, through which air flows in the direction indicated by the arrow 49.

The brake-pocket 42 shown in FIGS. 8 and 9 is constituted by four identical trapezoidal panels 43-44-45- 46 joined one to another to form a pyramidal structure.

At its upper end the brake-pocket 42 presents an anti-shock opening 47 through which air flows in the direction of the arrow 48.

In a sail such as that of a parachute, of an airship or of a boat, the normal pyramidal nozzle-pockets (FIGS. 1 to 3) elongated-pyramidal nozzle-pockets (FIGS. 4 and 5) and conical nozzle-pockets (FIGS. 6 and 7) have the effect of providing improved suspension means accelerating the flow of air and eventually modifying the direction of this flow.

Moreover the normal or elongated pyramidal pockets favor the spreading out of the sail owing to the volume of pressure which they contain, while the antishock conical pockets accelerate the discharge by permitting the avoidance locally of all thrust reducing the property of spreading given to the sails by the pyramidal nozzle-pockets.

The parachute sail 50 shown in FIG. 10 comprises a plurality of nozzle-pockets shown in FIGS. 1 to 7: normal pyramidal 1, elongated pyramidal 11 and conical 30, pockets so' orientated that all the escape orifices cause the escape of the air to be directed towards the rear of the sail as indicated by the arrow 51.

The flow passing through the escape orifices leads, in the course of flight, to the creation of a horizontal displacement component tending to pull the parachute in the direction of the arrow 40. Taking into account the displacement in flight it will be understood that the parachute 50 has a longitudinal axis 5252, a transverse axis 5353 and consequently forward and rear parts situated on either side of the transverse axis 53 53.

The parachute sail shown in FIG. 10 has in plan the form of a multiple-sided polygon which can be drawn in a circle. It could also have some other form which could be drawn in a curve, an ellipse for example.

At its edge the sail 50 presents an inflated leading edge 54 (after assembly of these front elements shown in plan before assembly in FIG. 10) a notch 55 at the rear, such as is described in the French Pat. Application filed on the 4th Oct., 1968 under the No. PV 168,720 and having as its title: Parachute with improved air circulation and lateral stabilizing panels 56-57 (also shown in plan) before assembly situated symmetrically in relation to the longitudinal axis 52 and as described in the French Pat. Application filed on the 20th Nov. I968 under the No. PV 174,465 by the same inventor under the title: Automatically guided parachute.

In its central part the sail 50 anti-shock escape slots 58.

In the sail shown in FIG. 10 the conical nozzlepockets 30 are grouped at the center and along the longitudinal axis 52 while the normal and elongated pyramidal nozzle-pockets 1 and 11 are disposed approximately in a circle, respectively in the rear part and the forward part of the sail.

The normal pyramidal nozzle-pockets 1 have square bases of the same dimensions and the elongated pyramidal nozzle-pockets have rectangular bases of double the surface of those of the preceding pockets. To assist assembly the pockets and the square elements also includes the usual constituting the remainder of thesail are arranged in accordance with a square grid.

The sail 50 includes as is usual leading edge shroud lines 59 and if need be central shroud lines 59 and if need be central shroud lines (such as are shown at 60 in FIG. 1) able to ensure a greater security in opening and also serving to control the increase in the propulsive suspension.

Further the canopy includes guide lines 61 enabling the user to modify as he likes the cross-section of the escape orifices of one or more of the elongated pyramidal nozzle-pocketd 11. These lines 61 pass through rings 62 fixed to the free edge of the panels definin g the escape orifices.

The sail of the parachute shown in FIG. has the great advantage of perfect stability in the face of the wind. Moreover it is very easily directable and opens very rapidly practically without shock.

The sail 63shown in FIGS. 11 to 13 can be used as a support for advertising material. It is made in the same way as that shown in FIG. 10. It includes, as shown in FIG. 12,-central lines 60 enabling the user to modify the shape of the central part of the sail.

By pulling with a suitable rhythm and amplitude on the lines 60 by means of rubber balls 64 fixed to the lines at the level of the user, the latter brings the center of the sail into a position such as that shown in broken lines and brings about, on the under side, a flow from the center towards the edge, which has the advantage of inducing an acceleration of the sustaining and propulsive flow by the increase of the supplementary volume, thus very considerably increasing the possibility of the sail gliding.

The publicity sail of FIGS. 11 to 13 includes in particular normal pyramidal nozzle-pockets 1 and concical nozzle-pockets 30. It also includes variants 1a of the normal pyramidal nozzle-pockets which differ from the latter in that their escape orifices are divided in two by a central connection 65, and lateral stabilizing panels 66 of which the position of use is shown in P16. 13.

In the case of sails for boats, and particularly in that of a spinnaker sail, these preferably comprise normal and elongated pyramidal nozzle-pockets withescape orifices directed all in the same direction or towards converging directions on the outer surface of the spin- I naker. With either of these arrangement one considerably increases the thrust of the spinnaker.

Of course the invention is not limited to the examples described and illustrated, it is amenable to numerous variations available to anyone skilled in the art, following the lines envisaged and without departing from the scope of the invention. i

What is claimed is:

1. Means for increasing the thrust. and/or sustaining power of sails such as in particular those of parachutes, airships or boats, comprising a plurality of pockets constituting at least part of the sail and each pocket being generally of conical or pyramidal shape with its concave side facing towards the inside of the sail, and including at least one normal pyramidal nozzle-pocket having its inner side facing towards the pressure side of the sail, said pocket having the form of a pyramid constituted by several adjacent panels of generally trapezoidal form, and said pocket having an air escape opening at the base of one of said panels an anti-shock openinssituated in its u per part.

Means accor ing to claim 1, including at least one elongated pyramidal nozzle-pocket constituted by several adjacent panels each having, in plan, a generally trapezoidal form, said pocket having at the base of one of its end panels an escape orifice and in the neighborhood of the end of its upper edge an antishock opening.

3. Means according to claim 1, including at least one conical nozzle-pocket constituted by two panels one with a triangular notch and the other triangular, incurved on the first and presenting a free edge defining an escape orifice.

4. Means according to claim 1, including at least one pyramidal brake-pocket, constituted by several adjacent panels each having, in plan, a generally trapezoidal form, said brake-pocket having solely an antishock opening situated in its upper part.

5. Means according to claim 3, including pockets with square bases and elongated pyramidal nozzlepockets having rectangular bases of the same dimensions, their sides being respectively equal to and twice as large as the size of the pockets with square bases.

Claims

1. Means for increasing the thrust and/or sustaining power of sails such as in particular those of parachutes, airships or boats, comprising a plurality of pockets constituting at least part of the sail and each pocket being generally of conical or pyramidal shape with its concave side facing towards the inside of the sail, and including at least one normal pyramidal nozzlepocket having its inner side facing towards the pressure side of the sail, said pocket having the form of a pyramid constituted by several adjacent panels of generally trapezoidal form, and said pocket having an air escape opening at the base of one of said panels an anti-shock opening situated in its upper part.

2. Means according to claim 1, including at least one elongated pyramidal nozzle-pocket constituted by several adjacent panels each having, in plan, a generally trapezoidal form, said pocket having at the base of one of its end panels an escape orifice and in the neighborhood of the end of its upper edge an anti-shock opening.

4. Means according to claim 1, including at least one pyramidal brake-pocket, constituted by several adjacent panels each having, in plan, a generally trapezoidal form, said brake-pocket having solely an anti-shock opening situated in its upper part.

5. Means according to claim 3, including pockets with square bases and elongated pyramidal nozzle-pockets having rectangular bases of the same dimensions, their sides being respectively equal to and twice as large as the size of the pockets with square bases.