PARACHUTE WITH SEGMENTED SLIDES

Description

technical field

[0001] The present invention relates to parachutes, which can be applied to various uses such as the controlled descent of a load until it is brought to the ground, in particular equipment (cargo parachute) or personnel (troop parachute), the slowing of the fall of a load by an extraction parachute before the deployment of the parachute used for landing (space parachute), or the slowing of an aircraft just after its landing (brake parachute).

[0002] Parachutes compatible with this invention include, in particular, hemispherical, square, cross, triangular or any other type of parachute except "wing" type parachutes, given their different opening kinematics, their construction partitioned by cells with little air volume to fill.

[0003] The present invention aims to provide a parachute that sequences the parachute's expansion in a repeatable manner during its deployment, limiting the descent, i.e., the loss of height during the expansion. Previous techniques

[0004] We know of parachutes whose gliders allow deceleration by using their aerodynamics in order to slow down and sequence the unfolding of the parachute canopy during its descent deployment.

[0005] These systems use a continuous slider, annular or circular in shape, inserted on all the suspension lines with a fabric surface generating aerodynamic drag.

[0006] This continuous glider solution with aerodynamic drag generation is nevertheless not applicable to drops at very low altitude due to a delay that is too long, increasing the times of unfurling and causing excessive lowering, i.e., excessive losses of height during the unfurling phase.

[0007] Other systems allow for braking of the opening by using a mechanical block or a pyrotechnic system to slow down the opening, consisting for example of a line running the entire length of the leading edge of the parachute canopy to tighten it and prevent its opening too quickly, this line must nevertheless be mechanically released after a few seconds.

[0008] These types of mechanical or pyrotechnic systems have many constraints: the addition of mass, the need for a complex assembly to be initialized at the time of release, the delicate use of pyrotechnics, and above all a very high cost.

[0009] The various types of solutions available on the market and described above result in a significant slowdown in opening or a complexity of implementation, making them incompatible with drops at very low altitudes. To enable these low-altitude drops, current best practices show that parachutes are not equipped with the device described above, leading to numerous burns and tears in the fabric, particularly the canopy and suspension lines, caused by poor sequencing of the deployment phase and an unpredictable, excessively rapid, and therefore violent, kinematic process.

[0010] They are therefore unsatisfactory and leave unresolved drawbacks that are all the more frequent when using a cluster of parachutes grouped together to carry a common load. US 7000872 B1 describes a circular parachute comprising a circular canopy with a skirt band and a plurality of Y-shaped main lines connected to the skirt band and converging downwards at a line junction. Each main line includes a lower segment that divides into at least two upper segments. A reduction device, generally planar, designed to slow the canopy's opening defines a plurality of openings through which the main lines extend. The reduction device comprises a strip of material folded into several strip segments arranged in a five-pointed star configuration.Ring-shaped brass eyelets extending through the junctions of the band segments form openings intended to receive the suspension wires. Description of the invention

[0011] The invention aims to overcome at least some of the aforementioned disadvantages and to offer a parachute capable of combining the advantages of speed, simplicity and reliability for its implementation, even in use in clusters and for low-altitude dropping.

[0012] In view of the foregoing, the invention relates to a parachute according to claims 1 or 2.

[0013] In another embodiment, the fastening means comprise a strap and the passage elements are formed by eyelets passing through said strap.

[0014] Advantageously, the slider is against the leading edge.

[0015] Preferably, the distance between two passing elements of the same slide is strictly less than that separating the first ends of two suspension lines at the leading edge.

[0016] For example, there are three, four, or five gliders.

[0017] The parachute may also be designed so that the attachment points are made of rope or fabric.

[0018] Preferably, the parachute includes a riser to which are connected on one side the second ends of the suspension lines and on the other side the load.

[0019] The invention also relates to a cluster of these parachutes in which the respective risers are connected to the same load. Brief description of the drawings

[0020] The invention will be better understood upon detailed study of an embodiment taken by way of non-limiting example and illustrated by the accompanying drawings, in which: [ Fig 1[ ] depicts a parachute with five sliders being filled during a descent, viewed from below. Fig 2 ] represents a cluster of three parachutes during a descent, viewed from the front. Fig 3 ] represents a first embodiment of the slide. Fig 4 ] represents a second embodiment of the slide. Detailed description

[0021] We refer to the figure 1 which illustrates a parachute 1 according to the invention, which comprises a canopy 2 having a leading edge 3 and a trailing edge 4 which is opposite the leading edge 3.

[0022] The leading edge 3 is the one intended to deflect the air during a descent with the parachute 1, so as to direct the air towards the center of the canopy 2 to unfold it.

[0023] Too rapid an expansion of sail 2 can occur if speed increases, causing too much air to enter sail 2 and leading to an overly abrupt opening, exposing it to a high risk of tearing.

[0024] The parachute 1 has suspension lines 5, each having a first end 6 attached to the leading edge 3 and a second end 7 intended to carry a load 10, which may be, for example, equipment or personnel.

[0025] Preferably, the parachute 1 includes a riser 9 to which are connected on one side the second ends 7 of the suspension lines 5 and on the other side the load 10.

[0026] The elevator 9 allows the load 10 to be centered vertically on the center of the sail 2 and the restraining forces exerted by the suspension lines 5 on the load 10 to be distributed in a balanced way.

[0027] The parachute 1 also includes at least two gliders 8 comprising suspension line passage elements 12 connected to each other by attachment means 11.

[0028] Each of the passage elements 12 of the gliders 8 is crossed by one of the suspension lines 5.

[0029] Each slider 8 is thus free in translation relative to each of the suspension lines 5 which passes through its passage elements 12, on which the slider 8 can slide under the effect of gravity and the force generated by the spacing of the suspension lines.

[0030] More specifically, each glider 8 is adapted to be able to glide along the suspension lines 5 which pass through the passage elements 12 from the first ends 6 of said suspension lines 5 to their second ends 7 under the effect of gravity and the force generated by the spreading of the suspension lines when the parachute 1 begins a descent, tensioning the suspension lines 5 under the effect of inflation of the canopy 2.

[0031] The parachute 1 is thus devoid of any fabric or canopy extending inside the volume formed by the suspension lines 5 under the canopy 2, as is the case in various state-of-the-art aerodynamic glider parachutes.

[0032] The presence and sliding of the sliders 8 make it possible to make the unfolding of the sails 2 of the families of parachutes mentioned above more reliable by limiting the degradation of the fabric of the sail 2 and the suspension lines 5.

[0033] They also help to reduce shocks to the unfurling of sail 2 when release speeds are high and to allow a stable descent speed to be reached more quickly, which is particularly useful for low altitude releases, i.e. less than about eighty meters from the ground.

[0034] The slider 8 can be butted against the leading edge 3, as is the case on the Figure 1 .

[0035] The slider 8 is in particular against the leading edge 3 when it is folded before use, and in the very first phases of descent during a parachute 1 release.

[0036] The positioning of a given slide against the stop allows the movement of the portion of sail 2 whose suspension lines 5 are connected to this slide 8 to be blocked during the first seconds of the opening phase, which reduces the air resistance of the leading edge 6 and therefore slows down the opening of this portion of sail 2, and thus reduces the shock at the opening of sail 2 which could cause it to tear or turn into a butterfly in the case of an unsequenced opening.

[0037] Sail 2 is classically divided into 14 sections, and the number of sections 14 is equal to the number of suspension lines 5.

[0038] By "fuse" we mean an element of the parachute 1 to which the suspension lines are attached and consisting of one or more assembled pieces which allow the parachute 1 to have a leading edge 3 and a trailing edge 4.

[0039] The number of gliders 8 is advantageously between fifteen and twenty-five percent of the number of spindles 14.

[0040] Indeed, tests of an annular slider, that is to say a single slider as in the prior art, and of an annular slider divided in two, have shown their ability to strongly delay the opening of the sail to the point of preventing it completely, resulting in a non-opening of the sail and an impact of the load on the ground.

[0041] For these tests, even though development could have been achieved if the drop altitude had been higher, they demonstrate the inadequacy of two gliders for low-altitude drops.

[0042] Tests by dividing the glider into three, four and five portions made it possible to perfectly time the unfolding, unlike the glider parachutes with aerodynamic drag generation, annular or circular of the prior art which are not suitable for low altitude drops.

[0043] Having these numbers of sections frees up the constraints on the leading edge 3 located between 2 sliders and allows the airflow to gradually fill the sail 2 during the descent and to expand the parachute 1 with a reasonable loss of height for low altitude.

[0044] The parachute 1 is thus formed of at least two gliders 8, with each of the gliders 8 connecting several suspension lines 5, and the number of gliders advantageously corresponds to fifteen to twenty-five percent of the number of gores 14.

[0045] In the example explained, the number of sliders 8 is ideally three.

[0046] The gliders 8 are thus placed on the suspension lines 5 in such a way as to form a segmentation alternating between areas equipped with gliders 8 and areas without gliders 8.

[0047] The sliders 8 can also be installed against the leading edge 3.

[0048] The invention also relates to a cluster, or grouping, of parachutes 13 as illustrated by the Figure 2 .

[0049] The parachute cluster 13 includes several parachutes 1 shared for carrying the same load 10.

[0050] Each of the respective 9 elevators of the parachutes 1 are therefore connected to the common load 10.

[0051] The greater the number of gliders 8, the less the development of parachute 1 or cluster 13 is delayed.

[0052] The fewer gliders there are 8 and the closer the passage elements 12 are, the longer the blossoming takes, because this configuration strongly constrains the blossoming of the sails 2.

[0053] Consequently, there is a low risk of degradation when using several 2 sails in a cluster 13, but the unfolding times are not compatible with a low-altitude release.

[0054] Conversely, the greater the number of gliders 8, and the further apart the passage elements 12 are, then the less constrained the sail 2 is, and the faster its development.

[0055] As a result, when opening in a position close to horizontal and / or in disturbed flow, the unfolding occurs too quickly and the sequencing between several sails 2 is uncontrolled, which can lead to degradation.

[0056] The optimum number of gliders (8) is therefore between fifteen and twenty-five percent of the number of spindles (14). Figures 3 and 4 illustrate two ways of implementing gliders 8.

[0057] In the first embodiment illustrated by the Figure 3 , the fastening means 11 comprise a strap and the passage elements 12 are formed by eyelets passing through said strap.

[0058] In the second embodiment illustrated by the Figure 4 , the passage elements 12 are formed of rings and the attachment means 11 comprise ropes connecting each two successive rings.

[0059] The distance between two passage elements 12 of the same slide 8 is for example strictly less than that separating the first ends 6 of two suspension lines 5 at the level of the leading edge 3.

[0060] The number of gliders 8 and the distance between these elements 12 are dependent on the timing objectives sought for each parachute 1.

[0061] A fairly short gap between each element 12 allows the leading edge 3 of the portion located between two sliders 8 to be stretched, and this tension allows the parachute 1 to fill from the center, and thus be solid and stable during its unfolding.

[0062] The number of passing elements depends on the number of suspension wires.

[0063] Depending on the size of the parachute 1 and the conditions of deployment (low altitude for cargo drop, or high altitude for space) the number of gliders 8 and the distance between the passage elements 12 differs.

[0064] At low altitudes it is desirable not to increase the development times of sails 2, and only to limit the degradations.

[0065] Parachute 1 may further provide that the attachment means 11 are made of rope or webbing or fabric.

[0066] The passage elements 12 are made of a material which provides significant mechanical resistance and adequate friction of the slides along the suspension wires 5, for example plastic.

[0067] The use of straps or halyards combined with passage elements 12 with metal rings or metal eyelets allows the possibility of folding the sliders 8, and therefore the entire parachute 1, without risk of damaging the canopy 2 with the passage elements 12.

[0068] We thus produce a parachute 1 which allows that, during the unfolding phase, the gliders 8 keep the suspension lines 5 grouped together and constrain the leading edge 3, thus slowing the unfolding of the sail 2 since this occurs by the progressive and central filling of the volume of air of the sail 2 and no longer, as in the prior art, by the random unfolding of the leading edge 3 subjected to the disturbed airflow.

[0069] This brief inflation delay allows the parachute 1 to have just enough time to approach its vertical position during the inflation phase, ensuring inflation under the best airflow conditions, since unlike the gliders usually used on parachutes, those of the invention do not have an aerodynamic action but only a mechanical one by using the friction of the suspension lines in the eyelets or rings.

Claims

1. A parachute (1) including a canopy (2) having a leading edge (3) and a trailing edge (4) which is opposite the leading edge (3), suspension lines (5) each having a first end (6) attached to the leading edge (3) and a second end (7) designed to bear a load (10), and at least one slider (8) having through-elements (12) for the suspension lines to pass through, said elements being connected to one another by attachment means (11), each of said through-elements (12) being passed through by one of the suspension lines (5) and being free to move in translation relative thereto, the slider (8) being designed to slide along the suspension lines (5) that pass through the through-elements (12) in the direction from the first ends (6) of said suspension lines towards their second ends (7) when the parachute (1) starts a descent, tightening and spreading apart the suspension lines (5) under the effect of inflating the canopy (2), characterised in that the canopy (2) has sections (14) and the number of sliders (8) is greater than or equal to two, the attachment means of each slider (8) being formed by a strap , each slider (8) being designed to slide along the suspension lines (5) that pass through the through-element (12) from the first ends (6) of said suspension lines (5) towards their second ends (7) under the effect of gravity and the force generated by the suspension lines spreading apart when the parachute (1) starts a descent, tightening the suspension lines (5) under the effect of inflating the canopy (2), each slider (8) being free to move in translation relative to each of the suspension lines (5) which passes through its through-elements (12).

2. A parachute (1) including a canopy (2) having a leading edge (3) and a trailing edge (4) which is opposite the leading edge (3), suspension lines (5) each having a first end (6) attached to the leading edge (3) and a second end (7) designed to bear a load (10), and at least one slider (8) having through-elements (12) for the suspension lines to pass through, said elements being connected to one another by attachment means (11), each of said through-elements (12) being passed through by one of the suspension lines (5) and being free to move in translation relative thereto, the slider (8) being designed to be able to slide along the suspension lines (5) that pass through the through-elements (12) in the direction from the first ends (6) of said suspension lines towards their second ends (7) when the parachute (1) starts a descent, tightening and spreading apart the suspension lines (5) under the effect of inflating the canopy (2), characterised in that the canopy (2) has sections (14) and the number of sliders (8) is greater than or equal to two, each slider (8) being formed by rings forming the through-elements and the attachment means (11) include rigging lines each connecting two successive rings; each slider (8) being designed to slide along the suspension lines (5) that pass through the through-element (12) from the first ends (6) of said suspension lines (5) towards their second ends (7) under the effect of gravity and the force generated by the suspension lines spreading apart when the parachute (1) starts a descent, tightening the suspension lines (5) under the effect of inflating the canopy (2), each slider (8) being free to move in translation relative to each of the suspension lines (5) which pass through its through-elements (12).

3. The parachute (1) according to claim 1, wherein the through-elements (12) are formed by eyelets passing through said strap.

4. The parachute (1) according to any of the preceding claims, wherein the slider (8) is in abutment with the leading edge (3).

5. The parachute (1) according to any of the preceding claims, wherein the distance between two through-elements (12) of a same slider (8) is strictly less than that separating the first ends (6) of two suspension lines (5) at the leading edge (3).

6. The parachute (1) according to any of Claims 1 to 5, wherein the canopy (2) has sections (14) and the number of sliders (8) corresponds to fifteen to twenty-five percent of the number of sections (14).

7. The parachute (1) according to any of Claims 1 to 6, wherein the attachment means (11) are made of rope or fabric.

8. The parachute (1) according to any of Claims 1 to 7, further including a riser (9) to which on the one hand the second ends (7) of the suspension lines (5) and on the other hand the load (10) are connected.

9. A parachute cluster (13) including a plurality of parachutes (1) according to Claim 8, the respective risers (9) of which are connected to a same load (10).