U.S. patent application number 14/682195 was filed with the patent office on 2015-12-31 for pyrotechnic device.
This patent application is currently assigned to Drew Defense GmbH. The applicant listed for this patent is Drew Defense GmbH. Invention is credited to Andreas Runck.
Application Number | 20150377598 14/682195 |
Document ID | / |
Family ID | 52823996 |
Filed Date | 2015-12-31 |
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United States Patent
Application |
20150377598 |
Kind Code |
A1 |
Runck; Andreas |
December 31, 2015 |
PYROTECHNIC DEVICE
Abstract
Parachutes for signalling rockets, for example, open in a jerky
manner, as a result of which the suspension lines (13) are exposed
to a heavy load. The invention envisages two suspension lines (14)
configured in an extensible, particularly rubber-band-like manner,
as a result of which the initially effective parachute surface area
is reduced, which causes the parachute canopy (12) of the parachute
(10) to open more slowly than with previous parachutes (10), which
in turn reduces the opening jerk of the parachute (10). In this
way, the suspension lines (13, 14) in particular, but also the
parachute canopy (12) of the parachute (10), are subject to less
load.
Inventors: |
Runck; Andreas;
(Bremerhaven, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Drew Defense GmbH |
Bremerhaven |
|
DE |
|
|
Assignee: |
Drew Defense GmbH
Bremerhaven
DE
|
Family ID: |
52823996 |
Appl. No.: |
14/682195 |
Filed: |
April 9, 2015 |
Current U.S.
Class: |
102/348 |
Current CPC
Class: |
F42B 10/56 20130101;
F42B 4/28 20130101; B64D 17/24 20130101; F42B 4/12 20130101 |
International
Class: |
F42B 4/12 20060101
F42B004/12 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 25, 2014 |
DE |
102014009168.6 |
Nov 18, 2014 |
DE |
102014016951.0 |
Claims
1. A pyrotechnic device having a rocket or a projectile, a
parachute (10; 25; 31) with parachute lines and at least one
signalling, illumination and/or observational means assigned to the
parachute (10; 25; 31), wherein the at least one parachute line is
more extensible than at least one other parachute line.
2. The pyrotechnic device according to claim 1, wherein the
extensibility of each extensible or more extensible parachute line
is at least twice as great as the extensibility of the at least
one, preferably all, other parachute lines and/or each extensible
or more extensible parachute line is extensible by at least 30% of
its starting length.
3. The pyrotechnic device according to claim 1, wherein the at
least one other parachute line is not or at least scarcely
extensible during deployment of the parachute (10; 25; 31).
4. The pyrotechnic device according to claim 1, wherein the or each
extensible or more extensible parachute line is extensible at least
to such an extent that its length can be increased by the diameter,
the greatest width or the diagonal of an outline surface area of
the parachute (10; 25; 31), particularly of a top surface (16) or a
cut piece of a parachute canopy (12; 26; 32).
5. The pyrotechnic device according to claim 1, wherein one or at
least two adjacent parachute lines exhibit a greater extensibility
than the other parachute lines.
6. The pyrotechnic device according to claim 1, wherein the
extension of all parachute lines, in particular the extension of
the extensible or more extensible parachute lines, falls in the
elastic range.
7. The pyrotechnic device according to claim 1, wherein the
elasticity of each extensible or more extensible parachute line is
the same, the elasticity of the or of each extensible or more
extensible parachute line is preferably such that when the
parachute (10; 25; 31) or the parachute canopy (12; 26; 32) is
completely opened, all parachute lines are at least the same
length.
8. The pyrotechnic device according to claim 1, wherein the at
least one extensible or more extensible parachute line is formed
from at least one rubber-band-like strand, in particular a rubber
band, and the at least one inextensible or less extensible
parachute line is formed from a rope, preferably a braided or woven
rope.
9. The pyrotechnic device according to claim 4, wherein the top
surface (16) or the cut piece of the parachute canopy (12; 26; 32)
has a preferably round or polygonal outline surface area, a
periphery (17) of the top surface (16) is preferably surrounded by
a collar (19), wherein a free lower periphery of the collar (19)
exhibits tails (22) and one end of a parachute line is fastened to
a tip (23) of each tail (22), the extensible or more extensible
parachute lines are preferably fastened to the tips (23) of two
adjacent tails (22).
10. The pyrotechnic device according to claim 1, characterized in
that the parachute lines are suspension lines (13; 14; 28; 29; 34;
35).
11. The pyrotechnic device according to claim 10, wherein lower
ends of the suspension lines (13, 14) opposite the ends of all
suspension lines (13, 14) fastened to the tips (23) of the tails
(22) of the collar (19) of the parachute canopy (12) are brought
together at a connection point (24) and the signalling,
illumination and/or observational means or an upper end of a
further parachute line carrying the signalling, illumination and/or
observational means, preferably a tethering line (15), is fastened
to the connection point (24), wherein the additional parachute line
or the tethering line (15) in particular is extensible,
particularly elastically extensible.
Description
STATEMENT OF RELATED APPLICATIONS
[0001] This patent application claims priority on and the benefit
of German Patent Application No. DE 10 2014 009 168.6 having a
filing date of 25 Jun. 2014 and German Patent Application No. DE 10
2014 016 951.0 having a filing date of 18 Nov. 2014.
BACKGROUND OF THE INVENTION
[0002] 1. Technical Field
[0003] The invention relates to a pyrotechnic device having a
rocket or a projectile, a parachute with parachute lines, and at
least one signalling, illumination and/or observational means
assigned to the parachute.
[0004] 2. Prior Art
[0005] The pyrotechnic devices referred to here are hand-fired
parachute rockets and also fired parachute cartridges or parachute
munitions with signalling means, illumination means and/or
observational means. The observational means may be cameras,
sensors or also measuring probes. The signalling, illumination or
observational means along with a parachute assigned to each of them
are fired up or on a ballistics trajectory by the rockets or
munitions. Thereafter, the signalling, illumination and/or
observational means fall slowly to earth hanging from the
parachute.
[0006] With known pyrotechnic devices of this kind, the signalling,
illumination and/or observational means are directly connected to
the parachute lines, wherein the parachute lines are formed from
ropes or other threads with no or no significant extensibility.
Because the parachute lines are either inextensible or only
slightly extensible, the parachute is completely effectively
deployed quickly and immediately, which leads to a jerky
deceleration of the signalling, illumination and/or observational
means. The loads on the parachute lines, but also on the parachute
canopy, are correspondingly great. This can lead to the failure of
the parachute, as a result of which the signalling, illumination
and/or observational means fall to the ground unbraked and
therefore very quickly. So that the risks described can be reliably
avoided, the parachute lines must have correspondingly thick
dimensions, which reduces the weight of the parachute to the
detriment of its load capacity, namely of the signalling,
illumination and/or observational means. This requires a
correspondingly large accommodating space in the pyrotechnic
device.
BRIEF SUMMARY OF THE INVENTION
[0007] Based on the above, the problem addressed by the invention
is that of developing a pyrotechnic device of the kind referred to
above, such that the risk of affecting the parachute detrimentally,
particularly during the opening or deployment phase of the
parachute, is removed or at least significantly reduced in a
simple, space-saving and cost-effective manner.
[0008] A pyrotechnic device for solving this problem is a
pyrotechnic device having a rocket or a projectile, a parachute
with parachute lines and at least one signalling, illumination
and/or observational means assigned to the parachute, characterized
in that at least one parachute line is more extensible than at
least one other parachute line. According to this, at least one of
the parachute lines is extensible and/or more extensible than the
other parachute lines. In particular, only at least one parachute
line is extensible, while at least one or all the other parachute
lines are inextensible or virtually inextensible. The at least one
extensible or more extensible parachute line means that the
parachute is not immediately decelerated with the full braking
effect and/or opens more slowly. The full effectiveness of the
parachute, particularly of its canopy, only comes into play in a
slow, time-delayed manner. The effective parachute surface area is
initially reduced by the preferably rubber-band-like elongation of
the at least one extensible parachute line. This initially leads
only to a slight delay in the dropping speed of the parachute with
the signalling, illumination and/or observational means suspended
therefrom. The at least one extensible or more extensible parachute
line then contracts little by little, preferably continuously, due
to the reducing fall velocity, as a result of which the parachute,
in particular the canopy thereof, only unfolds gradually, which
means that the signalling, illumination and/or observational means
fall to the ground consistently slowly over a prolonged period of
time. As a result of this, the risk of the parachute, in particular
the parachute canopy and/or the parachute lines, ripping can be
removed or at least reduced without any substantial structural
changes to the parachute and without additional space-requiring
means. The parachute only adopts its planned orientation in which
the extensible parachute lines have for the most part elastically
contracted once again and all parachute lines are therefore roughly
the same length or the non-extensible parachute lines are slightly
longer than the extensible parachute lines after a delay. This
planned orientation is only briefly referred to in the following as
a "completely deployed parachute".
[0009] It is preferably provided that the extensibility of each
extensible or more extensible parachute line is many times greater
than the extensibility of at least one, preferably all, other
parachute lines. It is thereby ensured that even when the other
parachute lines are extensible--even if only slightly--the at least
one more extensible parachute line can extend more and thereby
contributes to the general, time-delayed entry into full effect or
complete deployment of the parachute, in particular the parachute
canopy.
[0010] Alternatively or in addition, it may be provided that each
extensible or more extensible parachute line is extensible by at
least 30% of its unloaded total length (starting length). In other
words, this at least one parachute line can be extended elastically
to at least 1.3 times its original length during the opening of the
parachute. It is preferably provided that each extensible or more
extensible parachute line can be extended to more than 1.5 times
its starting length.
[0011] According to an advantageous embodiment of the invention, it
may be provided that at least one of the other parachute lines is
not or at least scarcely extensible during deployment of the
parachute. Only the at least one extensible or more extensible
parachute line then alters its length during the opening of the
parachute, as a result of which there is an initial reduction in
the effective parachute surface area, which substantially reduces
the load in the overall parachute system due to a smaller opening
jerk.
[0012] An advantageous possible embodiment of the device provides
that the or that each extensible or more extensible parachute line
is extensible at least to such an extent that its starting length
can be increased by the diameter, the greatest width or the
diagonal of an outline surface area of the parachute, particularly
of the parachute canopy. In this way, the at least one extensible
or more extensible parachute line can initially be extended so far
that the surface area of the parachute canopy initially runs
roughly in the longitudinal direction of the parachute lines or
else parallel or slightly obliquely to the flight path of the
parachute and is then continuously reoriented through the gradual
elastic regression of the extension of the extensible parachute
line or lines of the parachute or the parachute canopy until the
parachute becomes completely effective, in particular the complete
braking effect of the parachute canopy is achieved, at which the
outline surface area of the parachute canopy then extends roughly
at right angles transversely to the flight path.
[0013] In a preferred development of the device, it is provided
that at least two adjacent parachute lines or, alternatively, two
opposite parachute lines are extensible and/or have a greater
extensibility than the other parachute lines. In this way, an
initial orientation of the parachute canopy longitudinally to the
parachute lines or in the flight direction is reliably carried out.
The parachute canopy is practically pulled in the flight direction
preferably by two non-extensible or only slightly extensible
parachute lines, while a peripheral region of the parachute canopy
is held in the opposite direction to the flight path by the
extensible or more extensible parachute lines and the air forces
occurring, as a result of which the parachute does not immediately
open completely, but only little by little as the speed
decreases.
[0014] It is preferably provided that the extension of all
parachute lines, in particular the extension of the more extensible
parachute lines, falls within the elastic region. It is thereby
ensured that the initial extension, especially of the more
extensible parachute lines, is gradually reversed again, at least
for the most part, until the parachute is completely effective
and/or completely opened or else the parachute canopy is
deployed.
[0015] It is particularly advantageous if the elasticity of each
extensible or more extensible parachute line is the same,
preferably the elasticity of the or of each extensible or more
extensible parachute line is such that when the parachute is
completely open or the parachute canopy is completely deployed, all
parachute lines are the same length or approximately the same
length. This means that once the complete parachute braking effect
has been achieved, the parachute lines act as in the case of
traditional parachutes with all non-extensible or only equally
slightly extensible parachute lines.
[0016] An advantageous possible embodiment of the invention
envisages that the extensible or more extensible parachute lines
are formed from at least one rubber-band-like strand, in particular
a rubber band. By comparison, the parachute lines which are not or
only slightly extensible are traditionally formed from a line or a
rope, preferably a braided or woven rope, with virtually no
elasticity. Through the formation of the extensible or more
extensible parachute lines out of at least one rubber-band-like
strand or else a rubber band, at least this one parachute line
acquires an extensibility and elasticity that is substantially
greater than in the case of the other parachute lines which are
either not extensible at all or only to a negligibly small extent
within the framework of the forces occurring, wherein an extension
of this kind of the customary parachute lines lies below 1% of the
starting length.
[0017] An advantageous possible development of the device envisages
in the case of a parachute canopy with a top surface with a
preferably round, polygonal or elliptical cross section and a
collar surrounding the periphery of the top surface, that a free
lower periphery of the collar exhibits tails and one end of a
parachute line is fastened to a tip of each tail. With a parachute
of this kind, the extensible or more extensible parachute lines are
preferably fastened to the tips of two adjacent tails. This kind of
parachute configuration has surprisingly proved particularly
effective in connection with non-extensible or only slightly
extensible parachute lines, on the one hand, and extensible or more
extensible parachute lines, on the other. In this way, the delayed
braking action of the parachute, in other words the lengthening of
the time taken until the complete parachute canopy surface is
available for deceleration, is brought about particularly reliably
and as a result of this there is a reduction under all
circumstances in the opening jerk occurring when the parachute is
deployed.
[0018] Another possible embodiment of the device envisages
connecting together the ends opposite the ends of the parachute
lines fastened to the parachute canopy at a connection point.
Either the signalling, illumination and/or observational means can
be directly fastened at the connection point or also one end of
another parachute line, for example a tethering line, which carries
the signalling, illumination and/or observational means at the
opposite end. In this case, the at least one further parachute line
or tethering line, just as with a part of the parachute lines, may
be extensible, preferably elastically extensible. This
extensibility may, if necessary, be just as great as the extensible
or more extensible parachute lines. Through a further parachute
line or tethering line configured in this way, the shock absorption
or jerk damping during the opening or deployment of the parachute
can be brought about even more effectively. In particular, the time
required by the parachute to deploy completely can thereby be
increased.
BRIEF SUMMARY OF THE DRAWINGS
[0019] Preferred exemplary embodiments of the invention are
explained in greater detail below with the help of the drawings. In
the drawings:
[0020] FIG. 1 shows a perspective view of a fully deployed
parachute in a first exemplary embodiment,
[0021] FIG. 2 shows a side view of the partially unfolded parachute
with two extended suspension lines,
[0022] FIG. 3 shows a front view of the partially unfolded
parachute in FIG. 2 with two extended suspension lines,
[0023] FIG. 4 shows a side view of the completely unfolded
parachute in direction IV according to FIG. 6,
[0024] FIG. 5 shows a front view of the unfolded parachute in FIG.
4,
[0025] FIG. 6 shows a plan view of a parachute canopy of the
completely deployed parachute in FIGS. 1, 4 and 5,
[0026] FIG. 7 shows a perspective view of a partially deployed
parachute with an elastically extended suspension line according to
a second exemplary embodiment,
[0027] FIG. 8 shows a side view of the parachute depicted in FIG.
7,
[0028] FIG. 9 shows a perspective view of a partially unfolded
parachute with two elastically extended suspension lines according
to a third exemplary embodiment of the invention,
[0029] FIG. 10 shows a side view of the parachute in FIG. 9,
[0030] FIG. 11 shows a perspective view of a partially deployed
parachute with four elastically extended suspension lines according
to a fourth exemplary embodiment of the invention,
[0031] FIG. 12 shows a side view of the parachute in FIG. 11,
[0032] FIG. 13 shows a perspective view of a partially deployed
parachute with four elastically extended suspension lines according
to a fifth exemplary embodiment of the invention and
[0033] FIG. 14 shows a side view of the parachute in FIG. 13.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0034] The different exemplary embodiments of the invention are
explained below using the example of a hand-held parachute
signalling rocket or fired parachute signalling munitions.
[0035] The parachute signalling rockets and the parachute
signalling munitions in all exemplary embodiments exhibit a casing
with a charge or rocket motor which fires the parachute signalling
rocket or the parachute signalling munitions up into the air.
[0036] In all exemplary embodiments, a folded-together parachute
with at least one signalling means fastened thereto and, if
necessary, an expelling charge and a detonating agent are disposed
in the casing above the propellant or rocket motor.
[0037] In FIGS. 1 to 6 only the parachute 10 and the signalling
means 11 are shown after firing up and expulsion from the casing,
namely both in the partially deployed state (FIGS. 2 and 3) and
also in the completely deployed, entirely opened state (FIGS. 1 and
4 to 6).
[0038] The parachute 10 in the first exemplary embodiment (FIGS. 1
to 6) has a parachute canopy 12, four parachute lines configured as
suspension lines 13, 14 and a further parachute line configured as
a tethering line.
[0039] The parachute canopy 12 exhibits a top surface which is a
four-sided top surface 16 in the exemplary embodiment shown. The
peripheries 17 of the top surface 16 brought together at four
corners 18 in the present exemplary embodiment are of slightly
arcuate form, namely outwardly curved (FIG. 6). The top surface 16
is surrounded by a continuous collar 19 which runs roughly
perpendicularly to the top surface 16 and extends from the
peripheries 17 of the top surface 16. When the parachute 10 is
completely deployed or else opened (FIGS. 1, 4 and 5), the collar
19 points downwards starting from the top surface 16 to form the
downwardly open parachute canopy 12. In this way, a downwardly open
space is created in the parachute canopy 12, in which air gathers
when the parachute 10 with the signalling means 11 glides to earth
in a decelerated manner. In the four-sided top surface 16 shown
here, the collar 19 has four uniformly configured collar portions
20 which are linked together at seam edges 21 or fold edges
extending downwards perpendicularly from the corners 18 of the top
surface 16.
[0040] In the case of the parachute canopy 12 of the exemplary
embodiment of the parachute 10 shown in FIGS. 1 to 6, the free,
lower ends of each identical collar portion 20 are provided with a
triangular tail 22 which at its lowest point, lying midway between
two adjacent edges, in the exemplary embodiment shown, the seam
edges 21, has a tip 23. The tips 23 of all four collar portions 20
lie on the same plane. When the parachute 10 is completely opened
and deployed, this plane lies with parallel spacing below the plane
through which all four corners 18 of the top surface 16 run (FIGS.
4 and 5) and ideally intersects at right angles with the dropping
direction of the parachute 10. An upper end of the four suspension
lines 13, 14 is fixedly connected to the tip 23 of each of the four
collar portions 20. The lower ends of all four suspension lines 13,
14 are brought together at a common connection point 24 and held
there. At the connection point 24, an upper end of the tethering
line 15 is connected to all four suspension lines 13, 14. The
signalling means 11 is fastened to a lower end of the tethering
line 15.
[0041] According to the invention, a few suspension lines 14 are
elastically extensible or substantially more extensible than the
other suspension lines. In the exemplary embodiment shown, only two
adjacent suspension lines 14 are configured in a selectively
extensible manner, while the two other suspension lines 13 are more
or less inextensible. They are only extensible within the framework
of what is customary for lines. Where non-extensible suspension
lines 13 are referred to in the following, these should be taken to
mean suspension lines 13 which are only minimally extensible,
namely to an unavoidable extent, but are not extensible to a
selective extent according to the invention, as is provided for in
the case of the two adjacent suspension lines 14.
[0042] The deliberately extensible suspension lines 14 are formed
from one or a plurality of rubber-band-like strands. In particular,
the extensible suspension lines 14 comprise rubber bands. The
extensible suspension lines 14 are therefore extensible in the
elastic range, so that after the elastic suspension lines 14 have
been extended, the extension is automatically reversed again. The
extensibility or elasticity of the extensible suspension lines 14
may be such that the extensible suspension lines 14 are extensible
to twice their starting length in the unloaded state and/or twice
the length of the inextensible suspension lines 13 in the elastic,
in other words reversible, range. Each extensible suspension line
14 is preferably extensible by at least 30% of its unextended, in
other words contracted, starting length. In the exemplary
embodiment shown, the extensible suspension lines 14 can be
extended until their starting length can extend by the dimension of
the diagonal spacing of two opposite corners 18 of the top surface
16 of the parachute canopy 12, but at least the space between
opposite seam edges 21 of a collar portion 20. In the exemplary
embodiment shown, the elastic suspension lines 14 may extend
elastically in a manner similar to a rubber band to 1.5 to 2.5
times their starting length.
[0043] The virtually non-extensible suspension lines 13 are
produced from customary line material which is not or virtually not
extensible. These may be woven or braided lines or ropes. These
lines or ropes may, if necessary, be completely or partially formed
from high-tensile fibres, such as glass fibres or carbon fibres.
Suspension lines 13 produced from this are very light because as a
result of their high-tensile fibres they only have to display a
comparatively small diameter.
[0044] The lengths of the non-extensible suspension lines 13 and
also the extensible suspension lines 14 are of such dimensions that
when the parachute 10 is completely opened or deployed and the
parachute canopy 12 is then completely configured and once a
constant dropping speed of the parachute with the signalling means
11 suspended therefrom has been reached, the extensible suspension
lines 14 have constantly been shortened again, to the extent that
all four suspension lines 13, 14, including the extensible
suspension lines 14, are roughly the same length, so that the
connection point 24 of all four suspension lines 13, 14 lies
roughly centrally beneath the middle of the top surface 16 of the
parachute canopy 12, when the parachute 10 with the signalling
means 11 suspended therefrom floats slowly back earthwards to the
ground (FIGS. 1, 4 and 5).
[0045] The single tethering line of the signalling means 11 may be
formed from a substantially non-extensible rope or line. It is also
conceivable, however, for the tethering line 15 to be elastically
extensible in the same way as the suspension lines 14, wherein the
elasticity of the tethering line 15 may be greater or smaller than
that of the suspension lines 14.
[0046] Using the extensible suspension lines 14, the opening of the
parachute 10 after it has been fired upwards and ejected with the
signalling means 11 from the rocket casing takes place as
follows:
[0047] Because the parachute 10 has still not unfolded and is
preferably folded up following its ejection from the rocket casing,
said parachute falls with the signalling means 11 virtually
unbraked to begin with towards the ground. The parachute canopy 12
of the parachute 10 then gradually starts to deploy. As a result of
this, the suspension lines 13 and 14 are subject to tensile load.
In the case of the extensible suspension lines 14, this tensile
load causes them to extend elastically due to their extensibility,
as a result of which the initially effective parachute surface area
is reduced.
[0048] The lengthening of the elastic suspension lines 14 can go so
far that they are extended in respect of their unloaded starting
length to up to twice the length. The extensible suspension lines
11 preferably extend as a consequence of the braking force of the
as yet incompletely unfolded parachute canopy 12 so far that the
top surface 16 of the parachute canopy 12 extends roughly in a
plane longitudinally or slightly obliquely to the dropping
direction of the signalling means 11 (FIGS. 2 and 3). In this case,
the parachute canopy 12 is roughly stretched between the longer
extended suspension lines 14 and the shorter inextensible
suspension lines 13. In this way, the configuration of the
parachute canopy 12 is changed such that its effective surface area
is smaller to begin with, so that the parachute canopy 12 flaps
more or less like a flag in the wind. This leads to an initially
only slight reduction in the dropping speed of the parachute 10
with the signalling means 10 suspended therefrom. The tensile load
of the suspension lines 13 and 14 then falls little by little, as a
result of which the suspension lines 14 extended in the elastic
region gradually contract and shorten again. In this way, the top
surface 16 of the parachute canopy 12 is increasingly pivoted and
moved into a roughly horizontal alignment, as a result of which
there is a time lag in the unfolding of the parachute canopy 12 and
therefore a slower opening or else deployment of the parachute 10,
as a result of which due to the downwardly open parachute canopy 12
an air cushion increasingly forms therein which further reduces the
dropping speed of the parachute 10 with the signalling means 11.
Further elastic shortening of the extensible suspension lines 14
takes place in this case.
[0049] As soon as the parachute 10 and the signalling means 11
suspended therefrom have reached a constant dropping speed, the
extension of the elastic suspension lines 14 is cancelled for the
most part, namely to the extent that all suspension lines, namely
the inextensible suspension lines 13 and the extensible suspension
lines 14, are roughly the same length and the connection point 24
of the ends of all suspension lines 13 and 14 and also the
signalling means 11 ideally suspend centrally beneath the parachute
canopy 12, in other words a lengthening of the tethering line 15 in
the direction of the parachute canopy 12 runs roughly centrally
through the top surface 16 of the parachute canopy 12. To this end,
it is preferably provided that the elasticity or extension
behaviour of the elastically extensible suspension lines 14 is
adapted to the weight of the parachute 10 and, above all, of the
signalling means 11 suspended therefrom. At least with this ideal
orientation of the completely opened and folded parachute 10 with
the signalling means 11 suspended therefrom, all four suspension
lines 13 and 14, even the more extensible, elastic suspension lines
14, are roughly the same length.
[0050] The exemplary embodiments in FIGS. 7 to 14 relate to
parachutes each having a parachute canopy made of a planar, flat
cut piece. This cut piece is preferably made of a suitably limp
material, for example a thin film or a thin fabric. In the
exemplary embodiments in FIGS. 7 to 14, the parachute canopy is
formed from a simple rectangular, preferably square, cut piece with
four corners. The cut piece may be a single piece, so without
seams, but it may also be made from a plurality of pieces sewn
together.
[0051] The parachutes in the exemplary embodiments according to
FIGS. 7 to 14 essentially differ only through the number and
arrangement of the parachute lines configured as suspension lines.
In particular, the exemplary embodiments differ in the number and
arrangement of the extensible suspension lines and more or less
inextensible suspension lines. In relation to properties, the
extensible suspension lines are comparable with, particularly
equitable with, the suspension lines 14 of the previously described
exemplary embodiment. In exactly this way, the inextensible
suspension lines correspond to the suspension lines 13 of the
preceding exemplary embodiment.
[0052] In the exemplary embodiment in FIGS. 7 and 8, three corners
of the four-sided cut piece of the parachute canopy 26 are assigned
non-extensible suspension lines 28. Only a fourth corner 27 of the
parachute canopy 26 is assigned an extensible suspension line 29.
Consequently, the parachute 25 has a total of four suspension lines
28, 29 which are brought together at the lower end to a connection
point 30 and connected there. This connection point 30 corresponds
to the connection point 24 of the parachute 10. At the connection
point 30, the signalling means 11 not shown in FIGS. 7 and 8 and
also the following FIGS. 9 to 14 can either be arranged directly.
However, it is also conceivable for a further parachute line to be
fastened to the connection point 30, in particular a tethering line
likewise not shown in FIGS. 7 to 14 in the manner of the tethering
line 15 in FIGS. 1 to 6, the lower end of said tethering line
supporting the signalling means.
[0053] As a consequence of there being only one extensible
suspension line 29 on the parachute 25 in FIGS. 7 and 8, during
deployment of the parachute canopy 26 only one corner 27 of the
parachute canopy 26 is initially folded up, while the other three
corners 27 remain at roughly the same height, due to the
non-extensible suspension lines 28. In this way, only part of the
parachute canopy 26 of the parachute 25 adopts a position during
the initial deployment and during the extension of the one
extensible suspension line 29 which initially reduces a delay in
the parachute 25. When the single extensible suspension line 29
contracts again slightly with a decreasing reduction in the
dropping speed of the parachute 25, the parachute canopy 26 adopts
its intended symmetrical position, in which the parachute 25 is
completely deployed and all four corners 27 of the parachute canopy
26 are located at roughly the same level through a virtually
complete reversal of the initial extension of the extensible
suspension line 29 and as a result the parachute 25 reduces the
dropping speed of the signalling means 11 to the maximum extent
possible and thereby decelerates the signalling means to the
maximum extent.
[0054] The parachute 25 in the exemplary embodiment in FIGS. 9 and
10 differs from that in FIGS. 7 and 8 only in that of the total of
four suspension lines 28, 29 two adjacent suspension lines 29 are
extensible. Otherwise, the parachute 25 corresponds to the one in
FIGS. 7 and 8. The same reference numbers are therefore used for
the same parts in the exemplary embodiment in FIGS. 9 and 10 as in
the exemplary embodiment in FIGS. 7 and 8.
[0055] Because in the parachute 25 in FIGS. 9 and 10, two adjacent
suspension lines 29 are extensibly configured, with the initial
deceleration of the signalling means 10, the entire parachute
canopy 26 is positioned obliquely to the vertical dropping
direction. This means that the parachute canopy 26 does not yet
deploy the full braking effect to begin with, so that the dropping
speed of the signalling means is gradually reduced and the
extension of the two elastically extensible suspension lines 29 is
reversed little by little until all suspension lines 28 and 29 are
roughly the same length and the parachute canopy 26 is fully
deployed, in that it is oriented transversely to the dropping
direction of the signalling means and the dropping speed of the
signalling means is thereby reduced to the maximum extent
possible.
[0056] The parachute 31 in FIGS. 11 and 12 has a parachute canopy
32 which corresponds to the parachute canopy 26 of the parachute
25. Consequently, the parachute canopy 32 is also formed from a
four-sided, preferably square, cut piece with four corners 33.
[0057] The parachute 31 has five parachute lines which are
configured as four extensible suspension lines 34 and a
non-extensible suspension line 35. The four extensible suspension
lines 34 are the same length. Moreover, the non-extensible
suspension line 35 is exactly the same length as the four
extensible suspension lines 35 in the non-extended state. The four
extensible suspension lines 34 are fastened to the four corners 33
of the four-sided, particularly square, parachute canopy 32.
Conversely, the non-extensible suspension line 35 is fastened with
an upper end in the center of the four-sided parachute canopy 32.
The lower end of the non-extensible suspension line 35 is connected
to the connection point 30 in exactly the same way as the
extensible suspension lines 34 which lead to the corners 33 of the
parachute canopy 32. It is, however, conceivable in the exemplary
embodiment shown that the central, non-extensible suspension line
35 is slightly longer than the extensible suspension lines 34 in
their unextended state. When the parachute 31 is fully deployed, in
other words when the outer suspension lines 34 are unextended, the
longer central suspension line 35 gives the parachute canopy 32 on
the underside, in other words more or less the windward side when
the parachute 31 is dropping, a concave shape.
[0058] During the initial deceleration, the four outer suspension
lines 34 are elastically extended, as a result of which the corners
33 of the parachute canopy 32 fold up, while the parachute canopy
32 is held down in the center by the non-extensible suspension line
35. In this way, when the suspension lines 34 are still extended,
the parachute canopy 32 adopts an initially convex shape in
relation to the windward side of the dropping parachute 31, in
which the underside of the parachute canopy 32 is curved downwards.
In this way, the dropping speed of the signalling means suspended
from the parachute 31 is initially reduced by only a relatively
small amount. During the subsequent gradual reversal of the elastic
extension of the extensible suspension lines 34, the corners 33 of
the parachute canopy 32 are pulled downwards and the parachute
canopy 32 is thereby practically inverted again, as a result of
which the parachute canopy 32 adopts a concave form on its lower
side once again and the braking potential of the parachute 31 is
thereby increased. The parachute 31 which is thereby completely
deployed then decelerates the signalling means to the maximum
extent possible, as a result of which the parachute 31 reduces the
dropping speed of the signalling means 11 in respect of the
depiction in FIGS. 11 and 12 with the suspension lines 34
extended.
[0059] FIGS. 13 and 14 show a further exemplary embodiment of a
parachute 37 which substantially corresponds to the parachute 31 in
FIGS. 11 and 12. The parachute 31 also has a square parachute
canopy 32 made of a preferably planar cut piece, wherein extensible
suspension lines 34 are fastened to the four corners 33 of the
parachute canopy 32.
[0060] Unlike with the previously described parachute 31 (FIGS. 11
and 12), with the parachute in FIGS. 13 and 14, four non-extensible
suspension lines 35 are provided. These four non-extensible
suspension lines 35 are all spaced apart from the four corners 33
of the parachute canopy 32 towards the center thereof. The
fastening points of the non-extensible, inner suspension lines 35
on the parachute canopy 32 may lie on imaginary connection lines
between two diagonally opposite corners 33 of the parachute canopy
32 in each case, but also on center lines of the four-sided cut
piece of the parachute canopy. Through this arrangement, during the
initial unfolding of the parachute 31, a central, four-sided part
of the parachute canopy 32 is held by the equally long,
non-extensible inner suspension lines 35 in a roughly planar
orientation transversely to the perpendicular dropping direction.
The four equally long outer extensible suspension lines 34 are
elastically extended during the initial deployment of the parachute
31, so that an outer annular region of the parachute canopy 32
between the fastening points of the inextensible suspension lines
35 on the parachute canopy 32 and the outer corners 33 of the same
is folded up or inverted upwards, as a result of which the
underside of the parachute canopy 32 takes on a convex form during
initial deployment.
[0061] Through the partially deployed or effective parachute 31
shown in FIGS. 13 and 14, the dropping speed of the signalling
means fastened to the connection point 36 directly or via a
tethering line is successively reduced, in that the extension of
the elastically extensible suspension lines 34 is reduced little by
little. Once the extension of the elastic suspension lines 34 is
cancelled, the suspension lines 34 are either just as long as the
non-extensible suspension lines 35 or slightly shorter, as a result
of which the parachute canopy 32 takes on a flat or else concave
form on the windward underside of the parachute canopy 32 with a
completely effective and fully deployed parachute 31. The parachute
canopy 32 is then practically conversely shaped, as in the
depiction in FIGS. 13 and 14 showing the partially effective
parachute 31. With this embodiment of the parachute canopy 32 which
is concave and inverted downwards on the underside, the parachute
31 produces its maximum braking effect, which allows the signalling
means suspended from the parachute 31 to drop to the ground at the
slowest possible dropping speed.
[0062] In the manner described above, parachutes are also
configured for parachute illumination rockets, parachute rockets
with observational means such as cameras, probes or sensors, for
example, and also parachute signalling projectiles, parachute
flares and parachute projectiles for observational means fired on a
ballistics trajectory, in that parachutes of this kind also exhibit
at least one elastically extensible suspension line and at least
one non-extensible or not substantially extensible suspension line.
The opening jerk of the parachute is thereby reduced in exactly the
same way as has been described above in connection with parachute
signalling rockets and parachute signalling munitions.
LIST OF REFERENCE NUMBERS
[0063] 10 Parachute [0064] 11 Signalling means [0065] 12 Parachute
canopy [0066] 13 Suspension line [0067] 14 Suspension line
(extensible) [0068] 15 Tethering line [0069] 16 Top surface [0070]
17 Periphery [0071] 18 Corner [0072] 19 Collar [0073] 20 Collar
portion [0074] 21 Seam edge [0075] 22 Tail [0076] 23 Tip [0077] 24
Connection point [0078] 25 Parachute [0079] 26 Parachute canopy
[0080] 27 Corner [0081] 28 Suspension line [0082] 29 Suspension
line (extensible) [0083] 30 Connection point [0084] 31 Parachute
[0085] 32 Parachute canopy [0086] 33 Corner [0087] 34 Suspension
line (extensible) [0088] 35 Suspension line [0089] 36 Connection
point
* * * * *