FIELD OF INVENTION.

The present invention concerns a device for launching tube especially for combat vehicles.

BACKGROUND OF THE INVENTION

The present invention has been developed in connection wit a smoke system for rapid self-screening of electromagnetic radiation from combat vehicles, especially in the visible spectral interval. The requirement for the self-screening smoke for combat vehicles of the future will, however, tak into account both the visible and infra-red spectral range i.e. in the range 0,4 - 14 micrometers.

For a crew serving their draft duty to get field practice performance, use and effect of such a screening smoke, the present invention has been developed in view of not only t produce a smoke system for multi-spectral self-screening o combat vehicles, but also to produce a cheap and simple practice ammunition for training in the field.

Smoke ammunition for screening if IR-radiation is, however connected to several disadvantages, especially in relation to negative influence on the environment. This problem, which is of a somewhat minor importance in war, becomes, however, increasingly amplified in peacetime, since there exists uncertainty about the toxicity and permitted exposu time for soldiers in such an IR-smoke environment. Accordingly there may arise problems for the users when th during field practice forget requirements for using gas¬ masks. The use of this kind of smoke in peace-time will thus have to be reduced to a minimum. Further, ammunition being connected to such IR-smoke may represent a fire haza on summer drills. Additionally, IR-ammunition will be relatively expensive to buy.

In connection with drills in peacetime there will conse-

quently exist a demand for an ammunition which is fire-safe, non-toxic and cheap. The requirement for IR-coverage must then be reduced or optionally removed, but a non-toxic smoke which may simulate the chosen IR-smoke system concerning the time for establishment, the pattern of spreading and the screening-time, even if it only screens in the visible or near-infrared spectrum, may give the crew of combat vehicles a practice which is an acceptable replacement for practice with a real IR-multispectral smoke-screening system.

Further, the invention concerns the production of a cheap and safe ammunition for practice which in a simple way may be adjusted to the existing launching tubes, and which in addition may be used as a smoke hand-grenade with nearly a free choice for the type of smoke-charge.

PREVIOUS TECHNIQUE

NO patent no. 139.502 concerns a smoke ammunition with a smoke body assembled from smoke charges giving slow and sustained together with rapid smoke production, respec¬ tively. However, this publication does not disclose anything about a launching device which may be combined for firing from a grenade tube and simultaneous use as a handgrenade, respectively.

From NO patent no. 142.929 there is known a smoke-cartridge which may be launched and ignited in the area which is to be smokescreened, the smoke cartridge after ignition being thrown forwards in opposite direction from an escaping driving gas. Here the smoke cartridge contains smoke bodies as well, giving both rapid smoke production and smoke over a prolonged time interval.

NO patent no. 142.928 concerns a smoke handgrenade com¬ prising a smoke charge being made of compact, easily ignitible smoke charge sections surrounding an explosive charge.

NO patent no. 142.930 concerns a unitary charge for screen¬ ing of vehicles giving invisibility for ones own vehicle from enemy fire and comprising a smoke cartridge having certain similarities with the smoke cartridge according to NO patent no. 142.929.

NO patent no. 145.521 concerns a smoke grenade which may be launched from a tank or another vehicle, comprising a spontaneous part and a slow-burning part.

GB patent no. 1.149.982 concerns a smoke-producing compound based on titaniu -tetrachloride, whereas GB patent appli¬ cation no. 2.056.632 concerns a smoke projectile where the is used titanium in connection with the smoke as well and where the side walls of the projectile is formed in such a way that the smoke obtains a special flow-path.

Even if these publications give an indication of special assemblies of smoke grenades and also of smoke-producing compositions which may be regarded as being relatively environmentally benign, the person skilled in the art does not finds no reference to a combined smoke-container/pract ice ammunition and smoke-container added a hand-grenade igniter, so that one alternately may use the smoke-cart¬ ridge/practice ammunition as a launching grenade from a launching tube, especially from combat vehicles, or as a hand-grenade smoke-bomb.

BRIEF DISCLOSURE OF THE INVENTION

As a basis for the present invention is thus not only the task to produce a practice smoke system comprising a non- toxic and very advantageous ammunition price-vice, but als the task to give a specification for an ammunition having such a flexible assembly that it may be adjusted to simula most of the relevant IR-smoke-screens which will be market in the future.

More significantly the goal according to the invention concerns producing a cheap and simple practice ammunition which on one hand may be fired from a launching tube independent of its calibre, and which on the other hand may be used as a smoke handgrenade with a broad spectrum of smoke charge types.

Preferably, the aim is to produce a smokegrenade with a launcher charge being combusted by an igniting cap, and the smoke grenade will then give the following advantages:

1: No expense-increasing electrical components being included in the grenade,

2: a simple structure,

3: cheap choice of materials and production,

4: reduced weight and volume compared to known technique,

5: simple adjustment both as a launching grenade and smoke handgrenade.

The tasks are solved according to the present invention by device of the initially specified kind, which according to the invention is characterized in the launching tube comprising a preferably releasably connected attachment tube for launching smoke containers and/or practice ammu¬ nition.

In other words there is according to the invention given a specificatipn of a combination of a smoke cartridge and a special launching tube or attachment tube. The attachment tube is mounted for multiple use and is secured releasably in an original launching tube. The smoke cartridge in itself is placed in the attachment tube and is fired therefrom by manipulating the firing system of the original launching tube.

If one on the other hand uses the cartridge as a smoke handgrenade, one holds in the part of the smoke ammunition which comprises a "handle" with one hand, and pulls out a safety catch with the other hand before throwing the ignit 5 smoke-cartridge.

Suitably the lower part of the attachment tube may be adjusted to fit the original launching tube with respect t calibre and form of the electrical contact points. The sa 0 smoke cartridge may thus be used in launching tubes of different calibres by merely changing the contact part in the attachment tube.

Further advantages and features of the present invention 5 appear from the attached patent claims and from the follo ing detailed description of embodiments disclosed in connection with the attached drawn figures.

SHORT DISCLOSURE OF THE DRAWINGS 0

Figure 1 shows a sectional view of a first embodiment of device for a launching tube according to the invention.

Figure 2a and 2b show a side view of a smoke cartridge fo 5 launching from an attachment tube and launching and throw by hand, respectively.

Figure 3 is a side view of a variant of an embodiment for smoke ammunition for launching from an attachment tube. 0

Figure 4 is a view similar to figure 3, but shows smoke ammunition adjusted to both launching an throwing by hand

Figure 5 is a section through a combined smoke handgrenad 5 and smoke ammunition for tank-launching tubes.

Figure 6 is a principal view of especially the contact pa of an attachment tube for launching spontaneous smoke

6 especially from tanks.

Figure 7 is a side view, partly sectioned, of a similar embodiment as in figure 6 for a device according to the 5 invention.

Figure 8 shows a section through an igniter house.

Figure 9 shows a detail of the igniter house from figure 8. 10

Figure 10 is a plane view of the igniter house shown in figure 8.

Figure 11 is a section through a clamp cooperating with the 15 igniter house.

Figure 12 is a side view of the clamp from figure 11.

Figure 13 is a plane view of the clamp from figure 11. 20

Figure 14. shows a section through a bottom part of a grenade cartridge.

Figure 15 is a view from the underside of bottom part shown 25. in figure 14.

DETAILED DISCLOSURE OF EMBODIMENTS

As is apparent from figure 1, showing a partly sectional 30 side view through a first embodiment of the device according to the invention, the invention is based on a special additional tube or attachment tube. With basis in a standard or original launching tube 1, especially for combat vehicles or optionally other rolling or floating vehicles, 35 there is fitted a preferably releasably secured attachment tube 2, which in its turn carries a smoke container 3 with practising smoke and/or practice ammunition.

The firing of the smoke ammunition 3 which is fastened to the attachment tube 2, which in its turn is placed in the launching tube 1, takes place in the usual way by operating the firing button which already exists in the combat vehicl switching on the current from the electrical supply 4, and the current will then pass through contact plugs 5 secured at the bottom of the launching tube 1 and be transferred to contact rings 6 mounted at the lower part of the attachment tube 2.

When there has been established a current connection betwee the contact plugs 5 in the launching tube 1 and the contact rings 6 on the attachment tube 2, a solenoid 8 will be supplied with current and establish the required electro- magnetical field for the solenoid core 7 to move rapidly forwards against an ignition pin 9 being situated at the centre of the attachment tube 2, and which by its movement forwards impinges against and perforates an ignition cap 11 in the bottom of the smoke grenade or the smoke ammunition 3. The ignition cap 11 will then be activated and ignites an ejector charge 12 in the bottom of the smoke grenade 3, which accordingly is fired out as the fastening clamp 3f o the bottom lid of the expeller grenade simultaneously is broken off. The heat from the expeller charge 12 ignites delay element 13 which after being burnt through, ignites the detonation charge 14 itself in the smoke grenade 3 leading to the smoke cartridge or smoke grenade 3 being blown apart in the firing trajectory of the smoke cartridg with the resulting scattering of smoke material 15 being present inside the ejectable smoke grenade 3.

The attachment tube 2 comprises, in relation to the ejecti device, a comparatively short ejector part 2a, e.g. of the size 7 - 12 cm, and a contact unit 2b carrying the above mentioned contact rings 6 which in their turn are fitted t the contact points 5 in the launching tube l, together wit an ignition mechanism 2c which inter alia comprises the above mentioned ignition pin 9 which in its turn cooperate

with the contact unit 2b.

The ejector part 2a of the attachment tube 2 has mainly the form of a pipe, where a section of the pipe has for the main part a larger outside diameter than the inner diameter of the launching tube 1, so that the attachment tube 2 easily may be inserted into launching tube 1, the ejector part 2a simultaneously carrying an outer mantle section 20 having a diameter large enough for coming into fixed contact with the muzzle part of the launching tube 1 by inserting the attachment tube 2 into the mentioned launching tube 1.

The mantle section 20 on the attachment tube 2 is formed with a first radially extending section 20a passing into an axially rearwards extending part 20b for producing a sealing mantle surrounding and overlapping the muzzle part of the launching tube 1, the rearwards extending mantle part 20b simultaneously being equipped with securing devices, e.g. threaded screws 10.

Since the mantle section 20 on the attachment tube 2 may cover the edge of the permanently mounted, original launch¬ ing tube 1, the ejector tube 2 may be formed nearly in¬ dependently from the calibre of the original tube. The lower part of the attachment tube 2 , namely the contact unit 2b, may be adjusted to the original launching system with respect to the calibre and form of the corresponding electrical contacts. The same smoke cartridge may thus be used in launching tubes with different calibres by merely changing the contact unit 2b in the attachment tube 2.

Mechanical firing of the practice ammunition by using an attachment tube of the type being disclosed above, means a great reduction in the production costs for the ammunition. The cause is a significantly simplified construction and saving of labour operations since there are no electrical components included in the ammunition.

In the instant attachment tube the electrical components ar included in the mentioned contact unit, and may thus be re¬ used. The attachment tube may be removed when the firing practice is at an end and be cleaned by rinsing with water without any polishing of the original tube. By another practice firing, the same tube is mounted again, also implying a simplified maintenance and inspection.

It is to be understood that the insertion of the smoke grenade 3 is performed by the securing flange 3f at the bottom of the grenade coming into interaction with fitting grooves 2r in the securing clamp 26 which is shown in figu 1. It is important that the securing flange 3f on the bottom of the cartridge as well as the securing clamp comprise a securing mechanism which is safe and reliable a which simultaneously prevents deposits of black gunpowder from making problems when inserting a new grenade.

A special form of a securing flange may be one which is slitted to make a multiple of radially extending, com¬ paratively closely situated tongues. These are in unison strong enough to provide a secure and reliable attachment for the bottom of the cartridge in the groove 2r, but will easily break off and liberate the smoke cartridge when th is launched.

A further advantage of the device according to the inventi relates to the attachment tube 2 being formed to be loaded with different types of smoke grenades or ammunition, and the simplest type, shown in figure 2a, being formed to be fired from an attachment tube, comprises a smoke material enclosed in a plastic container, here referred to as 3a. When the container is exploded in the air there is immedi¬ ately formed an effective cloud of smoke. If the user wishes the ammunition to be thrown by hand as well, the cartridge may be modified as shown in the cartridge 3b of figure 2b, namely by mounting on a hand grenade igniter 21 in the lid. By using the cartridge 3b as a smoke hand-

grenade, the user is to hold the cartridge or the "handle" with one hand and pull the safety pin 23 with the other hand before throwing the cartridge. In both instances the smoke cartridge 3a or 3b is provided with a securing flange 3f for possible fastening to the securing clamp 26 in the attach¬ ment tube 2.

The smoke material in the said smoke grenade or -cartridges may be titanium tetra-chloride (TiCl ₄ or TTC) , a pyro- technical smoke charge being pressed into prefragmented discs which are ignited during dispersion, or other types of smoke charges based on pellets of red phosphorous, metallic powder, etc.

Preferably, the titanium tetra-chloride may be present in an aqueous phase, said phase, being in contact with moisture in the air, reacting spontaneously producing white smoke. The produced heat in this reaction is relatively insignificant. There exists accordingly no danger of igniting the vege- tation by using this smoke material. The toxicity of smoke based on the hydrolysis of TiCl4 is in addition very small. Presupposing that a lethal concentration of ZnCl ₂ -smoke (HC- smoke) is C _D , one will, even with a TiCl ₄ smoke concen¬ tration which is 50 x CD, only find insignificant unharmful changes of the lung tissue.

₀ n figure 3 there is shown a side view of a smoke ammu¬ nition, e.g. a practice smoke, for rapid and sustained screening of combat vehicles and personnel, being preferably formed for ^Launching from an attachment tube. This smoke ammunition is assembled from a smoke cartridge 3c, e.g. of the type shown in figure 2a, but is here extended with a further smoke cartridge 24 being secured, e.g. being screwed to the lid 22c on the lower cartridge 3c. When firing this compound smoke ammunition may first produce a spontaneous cloud of smoke followed by a continuous evolvement of smoke from the upper cartridge 24 when the unit has landed on the ground after the launching. Here the smoke cartridge 3c is

provided with a securing flange 3f as well.

In figure 4 there is shown an extended version of the smoke ammunition shown in figure 3, the compound unit here furthe comprising an igniter 31 for throwing by hand, a smoke outlet 32, a delay 33, an ignition channel 34 and a smoke charge 35.

In a cartridge giving smoke from the ground there is pre- ferably used a pyrotechnical smoke charge. This may produc TTC-smoke, HC-smoke or any other type of smoke.

In figure 5 there is shown further details of a variation o an embodiment for combined smoke handgrenade and smoke ammunition for a tank launching tube, i.e. a first smoke cartridge 3d with a lid 22d being secured to a further smok cartridge 24d. In addition there exists an igniter 31d, a delay 33d and an ignition channel 34d and firing charge 35. The parts for these simple smoke cartridges may here suitably be spray-cast in plastic material (e.g. PVC) , which, together with a simple assembly and relatively chea smoke material, will result in a low production price for the smoke cartridges. To effectuate the spreading of the smoke material, the smoke cartridges may also comprise "transport bodies" having a greater mass than liquid droplets in an explosion in the air, and may thus fly further from the blowing point. The smoke liquid which is connected with such "transport bodies" will be effectively spread and will give off smoke in a larger volume of air. The transport bodies may consist of e.g. porous pieces of coal with a diameter of e.g. 1 - 3 mm, and which is the smoke cartridge is saturated with smoke fluid. During the spreading these pieces expel most of the fluid again which, when in contact with air, immediately produces smoke.

In figure 5 there is also shown a central pipe 40 between the lid 22d and the bottom smoke cartridge 3d, the central pipe 40 containing an explosive charge, e.g. black powder

41. In the pipe section facing the bottom 41 there is situated a black powder delay 42 communicating with an expeller charge 43 in a depression 44 in the bottom 41. The expeller charge 43 is held in place with a smaller lid 45, in the central part of which there is mounted an igniter cap lid. When firing the previously mentioned igniting pin (see reference number 9 in figure 1) will ignite the igniter cap lid which in its turn ignites the expeller charge 43 and thereby the further igniting chain comprising the delay 42 which after approximately 1 second blows the cartridge 31 apart during spontaneous production of a white cloud of smoke and additionally ignites the smoke charge 35d giving a continuous smoke production after the grenade pieces have landed on the ground.

It is to be understood that all the indicated embodiments for smoke grenades, these being made as a combined smoke handgrenade or smoke ammunition for launching from tanks, may in a simple way be introduced into the upper part of the above mentioned attachment tube. Since this extra attach¬ ment tube, being introduced into the original launching tube and there being secured by hand, comprises a contact unit and corresponding ignition mechanism, especially an ignition pin being activated by the firing buttons in the tank, new grenades may be put into the attachment tube and secured e.g. by a downward push and twist. When firing the ignition pin impinges against the ignition cap in the grenade, leading to the grenade being ejected and ignited thereby clearing the attachment tube for a new introduction of ammunition through a suitable securing mechanism in the attachment tube.

It is thus to be understood that the launching tube in its launching section comprises such a securing mechanism for the grenade, formed in such a way that the bottom flange of the lower lid of the bottom smoke cartridge is secured in the attachment tube, said flange, as mentioned before, being weak enough to break during launching of the smoke grenade.

13

In figure 6 there is shown further details, especially for that contact unit 52b comprising the lower part of an attachment tube 52 being secured to the upper, shorter launching part 52a, and comprising contact rings 56 being fitted to corresponding contact points in the launching tub (see reference number 1 in figure 1) into which the attach¬ ment tube is to be inserted. Otherwise, the contact unit 52b comprises the solenoid 58 and the solenoid core 57 formed as a outwards-striking plunger. When activating th previously mentioned electrical firing system, the solenoi 58 will become activated and attract the plunger-formed solenoid core57 which will impinge against the igniting pi combusting the ignition cap in the cartridge which may be mounted into the launching part 52a of the attachment tube 52. The contact part 52b is secured to the launching part 52a of the attachment tube 52, e.g. by using securing plug of cast material or glue material, consequently making it possible to use the same smoke cartridge in launching tube with different calibres by merely changing the contact uni 52b in relation to the attachment tube 52.

In figure 6 there is also depicted a securing clamp 26a fo a smoke cartridge or ammunition which is to be positioned the launching part 52a. The securing clamp 26a may here, similarity with the securing clamp 26 shown in figure 1, b of the type which secures the grenade when inserting this into the launching part 52a by pushing downwards and twisting, e.g. by a securing flange on the bottom lid of t grenade being secured in the groove 22r in the securing clamp 26a.

In figure 7 there is shown a partially sectional side view of a corresponding embodiment as in figure 6, of an attach ment tube 102 comprising an upper shorter launching part 102a and contact unit 102b. Here 201 indicates a contact head, 202 a bottom plug and 106 contact rings. 204 is an intermediate ring and 205 represents the solenoid housing comprising a solenoid holder 206 and the solenoid core 107

A nut 208 is situated around the solenoid holder 206, an 209 represents an ignition pin housing cooperating with clamp 210 also surrounding the ignition pin 109 which at lower end includes a stop-washer 212 and a groove-leader 213. In the solenoid holder 206 there is taken out dril ings with different diameters, and the lower part of the ignition pin 109 has an axial portion cooperating with a coiled spring 214. On the outside of the part of the solenoid holder 206 lying above the nut 208, there is pl a screw-spring 215, i.e. between the top of the nut 208 the bottom of the ignition pin housing 209.

An ignition pin spring 216 is placed around the middle p of the ignition pin 109. Otherwise figure 7 shows a solenoid 108, a securing mantle 120 for a launching tube (not shown) , contact rails 220, recessed head screws 161 cylinder head screws 110 and threading pin 223.

In the figures 8, 9 and 10 there is shown further detail the ignition pin housing 209, figure 8 showing a section view through the ignition pin housing in similarity with what is shown in figure 7, whereas figure 9 shows a sect of the middle part of the ignition pin housing 209 where there is situated two pins 230 which are to protect the ignition pin shown in figure 7 when a launching of a smo cartridge is performed. Figure 10 shows a basic view of ignition pin housing 209, and from this figure and from figure 8 there appears that the ignition pin housing 209 formed with several openings 231 in the erect wall secti and several cut-out sections 232 removed from the bottom the ignition pin housing. Both sets of openings 231 and serve to reduce the problem with deposits from the black powder charge after firing, since these sections results the deposits taking place mainly outside of the area of actual ignition pin housing 209.

In the figures 11, 12 and 13 there are shown a sectional view through the clamp 210, a side view of the same clam

and a basic view of the same clamp, respectively. The section through the clamp 210 shown in figure 11, corre¬ sponds to the section being shown in figure 7, and it is to be understood that this clamp 210 is mounted resiliently against the screw spring 215 so that the actual clamp 210 may be pressed downwards in relation to the ignition pin housing 209 when the bottom of a smoke cartridge is pressed down into the same ignition pin housing 209, i.e. with the bottom part 245 of the smoke cartridge, in the way this bottom part 245 is depicted in the figures 14 and 15.

Figure 14 showing a section through a bottom part 245 of a smoke cartridge, indicates that the bottom part 245 com¬ prises a lower flange section 246 comprising four major notches 247a - 247d and several thin tongue sections 248 which in themselves build the securing flange 246 per se.

The bottom part 245 includes in addition a circular groove 249 running almost through the thickness of the material of the actual bottom part 245, so that the remaining material in the area for the groove 249 makes up an area of weakness which comes into effect when the cartridge is to be launch¬ ed.

In the middle part of the bottom 245 there is taken out a stepped aperture 250 being formed for insertion of a not shown ignition cap, e.g. as this is more closely shown in the previously discussed figure 5.

When inserting a smoke cartridge in the said ignition pin housing 209, the bottom part 245 of the smoke cartridge will be pressed down into said ignition pin housing, as two of the notches 247a - 247d may pass those projections 251a and 251b which are situated diagonally at the top edge of the ignition pin housing 209, the clamp 210 simultaneously being pressed downwards allowing the securing flange 246 of the bottom part 245 on the smoke cartridge to be twisted around and under said projections 251a and 251b, for thus b

a bayonetting effect to be fastened with its slitted securing flange 248 or 246 under the influence of a counter- pressure from the clamp 210 being under the influence from the previously mentioned screw spring 215.

In other words the insertion of a smoke cartridge will imply an elastic fastening of the bottom flange between the spring-influenced clamp 210 and the projections 251a and 251b on the ignition pin housing 209 proper.

When the ignition cap is influenced by the ignition pin 109, see figure 7, this will ignite the ejector charge, and this will cause the smoke cartridge to be launched from the launching tube 102, as one or more of the tongues 248 or 246 break off from the bottom part 145, as the circular section 251 surrounded by the groove 249 in the bottom part 245 simultaneously forms a recoil surface for the ejector charge, but gains support against the previously disclosed pins 230 extending from the bottom of the ignition pin housing 209, see figure 9.

In other words the limited middle section 251 of the bottom part represents a centring of the ignition pin, but also a support during the launching stage, and will probably break up into several pieces and be carried out by the backwash from the launched cartridge or optionally fall out from the ignition pin housing 209 after launching.

It is to be emphasized that there may be used a special kind of ignition cap, e.g. an ignition cap with a comparatively thin bottom ensuring that the striking power from the solenoid-driven ignition pin will penetrate the metal to produce the necessary striking power for igniting the ignition cap, and the thin bottom may optionally be provided with a small centred aperture being covered with a layer of enamel holding away humidity. This aperture may provide an entry for the tip of the ignition pin at the launching.

The ignition pin housing 209 is formed "airy" to let out th gas charge from the smoke cartridge during the launching. The elastic attachment further provides a varying distance relationship for the attachment of the slitted cartridge bottom, this elasticity permitting free introduction of the slitted flange section on the cartridge bottom even if the ignition pin housing 209 otherwise should be sooted be deposits of black gunpowder. It is further pointed out tha it is advantageous for the cartridge to be secured during the launching period thus providing a counter-pressure for the impingement of the ignition pin and thus ensuring a reliable ignition of the ignition cap. It has been found that the specific gravity of the cartridge alone is not sufficient to achieve a reliable cooperation between the ignition pin and cap. Because the ignition pin 109 is born up with a coiled spring 214 at its bottom and a screw sprin 216 around its middle section, there will be produced a suitable resiliency when the ignition pin on one hand strikes against the ignition charge and is returned to its original position and by this returning the recoil will be reduced via the mentioned coiled spring 214.

The mechanical firing of the smoke grenade or smoke cart¬ ridge implies a simple structure of the cartridge proper, without any soldering of contact points. The weight of the cartridge may be produced so low that it without difficulty may be used as a smoke hand grenade.

Since the present invention discloses a preferably releas- ably mounted attachment tube which may be inserted into the permanent original launching tube, said launching tube may, even with weak (marginal) bottom locks, be relieved from larger recoil forces. Since there is used an insertion tub the whole tube or tube combination may contribute to absorb the recoil forces.