US20020124761A1

US20020124761A1 - System for launching a charge or projectile with controlled slowing by line

Info

Publication number: US20020124761A1
Application number: US09/844,808
Authority: US
Inventors: Guy Valembois; Marc Pignol
Original assignee: Etienne LaCroix Tous Artifices SA
Current assignee: Etienne LaCroix Tous Artifices SA
Priority date: 2000-04-27
Filing date: 2001-04-26
Publication date: 2002-09-12
Also published as: EP1150091A1; FR2808323A1; CA2345871A1

Abstract

The present invention relates to a system for launching a charge or projectile (40), characterized in that it comprises:

a means (10, 12) of launching a charge (40),

at least one line (20) fixed by a first end (21) to a body (10) connected to the launch means and by a second end (22) to the charge (40), and

a slowing device (30) associated in a controlled manner with the line (20).

Description

The present invention relates to the field of systems for launching charges or projectiles.

More specifically, the present invention relates to the field of such launch systems for which it proves necessary to control the distance to which a charge is ejected or the dynamics with which a charge exits, for example by slowing down a projectile at a given distance.

Various proposals have already been made in an attempt at meeting this need.

However, so far as the applicant company is aware, no solution has yet proved to be entirely satisfactory from the standpoints of reliability, simplicity of operation, and cost.

The present invention improves this situation using a system comprising:

a means of launching a charge,

a line wound into a coil, fixed by a first end to a body connected to the launch means and by a second end to the charge, and

a slowing device associated in a controlled manner with the line so as to carry out controlled slowing of the charge or projectile.

According to another advantageous feature of the invention, the slowing device is associated with a limited portion of the line.

According to another advantageous feature of the invention, the slowing device is of the friction type.

According to another advantageous feature of the invention, the slowing device is made up of a rigid structure, for example of the annular type, equipped with a series of through-perforations through which the line is engaged, for example in a spiral, in a loop, in a sinusoid, or alternatively in any other appropriate configuration.

Other features, objects and advantages of the present invention will become apparent upon reading the detailed description which will follow and upon studying the appended drawings which are given by way of nonlimiting examples and in which: [0012]
FIG. 1 depicts a schematic view in longitudinal axial section of a device according to the present invention, [0013]
FIG. 2 depicts a view on a larger scale of a slowing device according to one alternative embodiment of the present invention, and [0014]
FIG. 3 depicts a view in transverse part section of this slowing device, on the section plane referenced III-III in FIG. 2.[0015]
The appended FIG. 1 shows a device according to the present invention comprising a [0016] body 10 forming a mortar centred on an axis O-O. The body 10 comprises, at its base, a pyrotechnic chain 12 capable, when implemented, of launching or propelling a charge or projectile 40 placed at the opposite end of the body 10.
Such a [0017] body 10 and pyrotechnic chain 12, which are known per se, can be embodied in numerous alternative ways. They will therefore not be described in detail in what follows. As a preference, the pyrotechnic chain 12 works by generating gas under pressure.
Likewise, the charge or [0018] projectile 40 may be embodied in numerous ways and will therefore not be described in detail in what follows.
As indicated earlier in the context of the invention, there is a [0019] line 20, a first end 21 of which is fixed to the body 10, for example near the pyrotechnic means 12 or on the base of the body 10, while the opposite second end 22 of the line 20 is fixed to the charge 40.
Furthermore, in the context of the invention, the [0020] line 20 is associated with a slowing device 30.
According to the particular embodiment depicted in the appended figures, the slowing [0021] device 30 is associated with a region of the line 20 some way between its two ends 21, 22.
The two portions of line referenced [0022] 23 and 24 respectively arranged on each side of the slowing device 30, are each respectively coiled in helices centred on the longitudinal axis O-O of the body and referenced 25 and 26 respectively in the appended FIG. 1.
More specifically still, according to the particular embodiment depicted in the appended figures, the [0023] slowing device 30 comprises a rigid roundel 32 of annular type centred on the longitudinal axis O-O of the body, and the overall plane of which runs at right angles to this axis. The roundel 32 has through-orifices 34 parallel to the longitudinal axis O-O of the body. There may thus be a number of through-passages 34 which may or may not be uniformly distributed over the roundel 32.
Of course, the number of [0024] passages 34 illustrated in the appended figure is non-limiting.
The intermediate region of the [0025] line 20 is wound, for example in a spiral, in a loop, in a sinusoid or alternatively in any other appropriate configuration, over the roundel 32, passing through certain selected passages 34 as illustrated in FIGS. 1 and 2.
The number of [0026] passages 34 and the spacing of the passages 34 chosen to accommodate the line 20 directly determine the slowing force applied, by friction, to the line, when the latter is pulled by the launching of the charge 40.
Thus, the system can readily be adapted to several applications by selectively choosing, according to the application adopted (and in particular according to the mass of the [0027] charge 40 and/or to the desired trajectory dynamics), which passages 34 are required in order to obtain the expected slowing force.
As can be seen in FIG. 3, the [0028] roundel 32 is preferably machined so that it has no sharp edges in the running path of the line 20. Thus, the passages 34 preferably widen at their respective entries and exits on the faces of the roundel 32, so that they meet these faces more or less tangentially and avoid damaging the line 20 as it runs. Likewise, the internal periphery 33 of the roundel 32, over which the line 20 also runs, is preferably rounded, for example in the form of a torus-shaped cap.
The way in which the device thus described works is, overall, as follows. [0029]
Initiation of the [0030] pyrotechnic charge 12 causes the region lying between the casing 10 and the projectile or charge 40 to become pressurized, causing this projectile or charge to be expelled.
The [0031] line 20 therefore uncoils freely from its coil 26 adjacent to the charge 40, while remaining slightly taut. To achieve this, the coil 26 may, for example, be coated with wax or resin, or with any other equivalent material.
When the [0032] coil 26 has been entirely paid out, the coil 25 adjacent to the base of the body begins to pay out through the slowing device 30.
During this phase, the [0033] line 20 travels through the passages 34. The successive windings of the line over the slowing device 30 create a tension force which controls the projectile stopping dynamics.
The projectile or [0034] charge 40 thus, first of all, while the first coil 26 is being paid out, rapidly gains speed (pyrotechnic effect), namely runs practically at constant speed due to the tensioning of the line as a result of the uncoiling of the coil 26, then experiences constant and sustained deceleration due to the combined action of the uncoiling of the coil 25 amplified by the slowing device 30.
Of course, the present invention is not restricted to the embodiment or to the particular application which have been described and illustrated in the appended figures but extends to cover any variant in accordance with its spirit. [0035]
Thus, the system may extend to an arrangement outside a launcher cartridge or [0036] body 10.
Furthermore, [0037] several lines 20 may be associated with one slowing device 30 and one single charge.
Likewise, one or [0038] more lines 20 may be associated with several slowing devices 30 inserted selectively along the length of the line 20 in order to control the slowing-down dynamics.

Claims

1. System for launching a charge or projectile (40), characterized in that it comprises:

a means (10, 12) of launching a charge (40),

at least one line (20), wound into a coil, fixed by a first end (21) to a body (10) connected to the launch means and by a second end (22) to the charge (40), and

a slowing device (30) associated in a controlled manner with the line (20) so as to carry out controlled slowing of the charge or projectile (40).

2. System according to claim 1, characterized in that the slowing device (30) is associated with a limited portion of the line (20).

3. System according to one of claims 1 and 2, characterized in that the slowing device (30) is associated with a region of the line (20) that is some way between its two ends (21, 22).

4. System according to claim 3, characterized in that the two portions of line (23, 24) located on each side of the slowing device (30) are each respectively coiled (25, 26).

5. System according to one of claims 1 to 4, characterized in that the slowing device (30) is of the friction type.

6. System according to claim 5, characterized in that the slowing device (30) is made up of a rigid structure (32) equipped with a series of through-perforations perforations (34) through which the line (20) is engaged, for example in a spiral, in a loop, in a sinusoid, or alternatively in any other appropriate configuration.

7. System according to one of claims 5 and 6, characterized in that the slowing device (30) comprises a rigid annular roundel (32) which has through-orifices (34), through at least some of which an intermediate region of the line (20) is wound, for example in a spiral, in a loop, in a sinusoid or alternatively in any other appropriate configuration.

8. System according to claim 7, characterized in that the roundel (32) has no sharp edges in the running path of the line (20).

9. System according to claim 8, characterized in that the passages (34) formed in the roundel (32) widen at their respective entries and exits on the faces of the roundel (32) so that they meet these faces approximately tangentially and avoid damaging the line (20) as it runs, and likewise the internal periphery (33) of the roundel (32), over which the line (20) runs is rounded, for example in the form of a torus-shaped cap.

10. System according to one of claims 1 to 9, characterized in that it comprises several lines (20) associated with a common charge (40).

11. System according to one of claims 1 to 10, characterized in that it comprises several slowing devices (30) inserted selectively along the length of the line (20) so as to control the slowing-down dynamics.

12. System according to one of claims 1 to 11, characterized in that the launch means comprises a body (10) forming a mortar and a pyrotechnic chain (12) capable, when implemented, of launching or propelling a charge or projectile (40).