WO2010149291A1

WO2010149291A1 - Ignition and activation unit for igniting red phosphor flares by means of a laser

Info

Publication number: WO2010149291A1
Application number: PCT/EP2010/003568
Authority: WO
Inventors: Michael Gowin; Jürgen Hofmann; Markus Jung; Nenad Prelic; Eric Ten Have
Original assignee: Rheinmetall Waffe Munition Gmbh
Priority date: 2009-06-26
Filing date: 2010-06-15
Publication date: 2010-12-29
Also published as: DE102009030868B4; DE102009030868A1

Abstract

Based on the idea that a further heat source is generally created during ignition by means of hot air, to which source a heat-seeking guided missile could respond, the present invention focuses on an ignition by means of a laser. According to the invention, a sufficiently great power density is applied to the surface of the RP flares by means of laser radiation, wherein laser optics (2) are integrated in order to allow distribution over a large area. An ignition or activation unit (100) suitable for such laser ignition of the flare comprises a combustion chamber (1) having a plurality of adapters (3) for receiving diverse laser optics (2).

Description

DESCRIPTION

Ignition or activation unit for lighting red-phosphor flares by means of a laser

The invention is concerned with the ignition of red-phosphorus flares (RP-flares), in particular ammunition-free active materials or Wirkkörpem example, for forming IR-deco-targets, by means of laser.

Red phosphorus (RP) has been used for military purposes for a long time, e.g. As in fog grenades, flares, etc. The purpose of ejecting flares is the diversion of approaching missiles. The ignition of the RP units usually takes place via an ignition or disassembly charge, which ensures that the RP units are optimally distributed and ignited for the respective purpose.

The use of such decoys in civil aviation is not possible because of the ammunition share, as explosives are not accepted in this context and international security agreements, etc. are respected.

Because of this, a new ignition concept was developed, which manages without explosive and / or pyrophoric materials for the ignition of RP / NC flares.

This new ignition concept is described in detail in DE 10 2006 004 912 A1. It is a system known to protect, in particular, large-scale flying platforms, such as aircraft, IR or radar-directed threats. The activation or ignition of the active body preferably takes place without contact. The ejection of the active body is then carried out pneumatically or mechanically. The active bodies themselves are ammunition-free packages which are ignited by means of hot air or a laser.

Further pursuing this idea, the invention has the object to show an ignition device or activation unit for ammunition-free active body / active masses. The object is achieved by the features of claim 1. Advantageous embodiments are shown in the subclaims.

Based on the idea that hot air firing is known to provide another source of heat to which the missile seeking heat seeks to respond, one's own path focuses on laser firing, although a thermal firing source of heat could be isolated and measures taken which make it possible to accelerate the necessary warm-up time of the thermal source. However, the firing of the flares by means of laser in principle avoids the creation of a further heat source on the outside of an aircraft, vehicle, etc.

Therefore, the invention is based on the idea of a Laseranzündung or activation by means of laser. A big advantage of a laser ignition is that a time-defined amount of energy can be dosed accurately in a simple manner. This allows a temporal resolution of the ignition process in the range <1 microseconds and thus ensures optimum efficiency of the ignition device.

The RP flares are thus exposed by means of laser radiation with a sufficiently high power density on its surface. By absorbing the laser radiation, the temperature of the RP flares increases, which causes ignition with self-sustaining combustion. For ideal ignition (activation) of the flares, the laser energy is directed to the largest possible portion of the surface. For this purpose, the laser radiation is shaped by appropriate optics so that an optimal distribution on the surface is achieved.

In addition to the advantages already mentioned, such as a fast reaction time without necessary lead times or a precisely defined introduction of energy, this solution enables an extremely flexible ignition configuration.

Reference to an embodiment with drawing, the invention will be explained in more detail. It shows:

1 is a side view of an activation unit,

2 is a plan view of the unit of FIG. 1,

Fig. 3 is a sectional view showing the combustion chamber of Fig.1. In the figures, an ignition or activation unit is marked with 100, consisting of a combustion chamber 1 and adapter (six) 3 for receiving various (six) laser optics 2 and a distributor plate 4 for preferably a compressed air distributor 5. Both can be attached via cylinder screws , For ventilation, the combustion chamber 1 is provided with a number of ventilation channels 9, but at least one, which are acted upon by means of angle (six) 8 with compressed air from the manifold 5. Unused openings can be closed with blanking plugs or countersunk screws. Denoted by 10 is a housing of the unit 100, which can be mounted on a plate 11 on an object, vehicle, etc.

The function of lighting or activating is as follows:

A Flare Pact consists in a first variant of about 150, for example, stacked Einzelflares (RP Flareblättchen), which are tied together with a fishing line in the center (hole about 5 mm).

The diameter of the flare package is approx. 30 mm. The leaflets are held together by, for example, three bows of fishing line. In order for the fishing line to be separated in any case during the movement past the laser source, the fishing line is preferably twisted on the ignition surface relative to the longitudinal axis. This can be achieved, for example, by twisting the flare package so that the fishing line is not parallel to the longitudinal axis of the flare package. In order to ensure optimal disintegration after separation, the lacing should only be performed on the surface of the flare package. An internal lacing should be avoided.

The flare (s) are pushed through the central channel (1) of the ignition unit 100 (housing 10) and are irradiated laterally with up to six laser beams through the optics 2. These laser beams ignite the individual flare leaflets and separate the fishing line. The planar energy input of the laser radiation accelerates the ignition process of the flare package and thus ensures a sufficiently fast rising edge of the beam line of the IR decoy target.

The gas purging on the one hand supports the ignition process and on the other hand prevents the contamination of the laser optics 2 by burned products. The laser source (s) and Control are spatially separated from the combustion chamber 1, the laser radiation is preferably transported via fiber optic cables or the like to the combustion chamber 1 and provided with a beam guide, which are connected by means of the adapter 3 with the combustion chamber 1. In order to avoid that a mutual influence of the laser radiation deteriorates the ignition, the beam paths have a lateral offset from the center of the central channel of the combustion chamber 1.

Alternatively, the flare package may be encapsulated by a fully combustible envelope (not shown). In this case, the ignition of the combustible shell or the flare package takes place from the outside over the upper side surface of the shell. The case may also contain an ignition aid to assist the flare ignition.

Claims

1. Ignition or activation unit (100) of red-phosphorus flares or active bodies by means of laser radiation, characterized by

• A combustion chamber (1) and several adapters (3) for receiving various laser optics (2), so

• An ignition of the flares or active body by means of laser radiation without contact in the passage through the combustion chamber (1).

2. An ignition unit according to claim 1, characterized in that a distributor plate (4) for at least one compressed air distributor (5) is integrated for gas purging.

3. Ignition unit according to claim 1 or 2, characterized in that for the ventilation, the combustion chamber (1) is provided with at least one ventilation duct, which are provided via angle (8) with compressed air from the distributor (5).

4. Ignition unit according to one of claims 1 to 3, characterized in that the beam paths have a lateral offset from the center of the central channel of the combustion chamber (1).

5. Ignition unit according to one of claims 1 to 4, characterized in that the laser optics (2) circumferentially evenly on the housing (10) and spaced from each other are mounted such that a uniform lighting of the flare or active body is realized.

6. An ignition unit according to claim 5, characterized in that six laser optics (2) are integrated.