GB2079419A - Pyrotechnic signalling devices - Google Patents

Abstract

A pyrotechnic signaling device comprises a hand held projector 1 and a magazine 5 slideably mounted thereon and which carries a plurality of signal cartridges. The projector has a T- shaped slot 12 and the magazine is provided with a complementary projecting portion 7 to enable the magazine to slide relative to the projector and bring each signal cartridge in turn into a position for firing by the projector. At one end of the projecting portion is a pair of pivot lugs which may bear against pivot bearings at one end of the slot so that the magazine may pivot about the lugs into a stowed position in which it lies closely alongside the projector. <IMAGE>

Description

SPECIFICATION Pyrotechnic signalling devices 'The present invention concerns pyrotechnic signall ing devices such as may be carried by persons for whom due to the nature of their occupations or pastimes, a need may arise to signal to other persons over large distances in order to summon assistance, send messages or otherwise.

A known pyrotechnic signalling device comprises a projector and cartridges with complementary screw threads. To prepare a cartridge for firing it must first be screwed on to the projector, an operation which requires time and a considerable amount of manual dexterity. Furthermore the case of the spent cartridge must be unscrewed from the projector before a further cartridge may be prepared for firing. Such complicated operational procedure is a disadvantage which may become critical in hostile environments and in use with heavily gloved hands.

The Applicant's copending UK Patent Application No. 24184/77 describes a pyrotechnic signalling device which overcomes at least some of the above drawbacks of the prior art device by providing a projector with a detachable magazine borne rotat ably thereon such that any one of a plurality of signal flares may be selected to be fired by rotation of the magazine. The device thus allows one or more of a series of signal flares to be fired without complicated and time consuming preparation and with an ease of operation suited to use in hostile and aggressive environments.

In the device of UK Patent Application No 24184/77 it is intended that the magazine is removed from the projector when not in use and placed in a stowed position on the projector. However, the magazine must be completely detached from the projector to transfer it from the operative to the stowed position and vice versa, and hence the magazine may be mislaid or dropped during preparation. Furthermore with a rotatable magazine the signalling device is not of a compact and stream-lined shape even when in the stowed position. This is particularly disadvan tageous with respect to the storage and transporta tion of the device especially in situations where economy of space is essential such as in packs of safety equipment.

The present invention seeks to provide a signalling device by which a plurality of signals may be fired, requiring a minimum of manual dexterity for prepa ration; and capable of being made particularly compact and convenient to carry.

According to the present invention there is pro vided a pyrotechnic signalling device comprising a magazine bearing a plurality of signal cartridges and a projector for firing the cartridges one at a time, wherein in an operational condition the magazine is borne slideably on the projector so that upon sliding of the magazine relative to the projector each cartridge can be brought in turn into a position for firing by the projector.

Preferably the projector and the magazine are provided one with a slot and the other with a rnmnl,,m,'ntarv nroiectina Dortion, the projecting portion being slideable in the slot and captive therein in the operational condition.

Advantageously the projector and the magazine are provided one with lugs extending laterally one on each side of the axis of sliding and the other with a complementary pair of pivot bearings in which the lugs are engageable, whereby the magazine can pivot about the common axis of the lugs in their respective pivot bearings between operational and stowed positionS.

Preferably the lugs engage their respective pivot bearings when the magazine reaches a limit of sliding movement in one direction.

It can then be arranged that the magazine can be removed from the projector by sliding in the other direction.

In a convenient arrangement the lugs are slideable in the slot, and the pivot bearings are continuous with the slot and defined by an end stop therein which the lugs cannot pass.

Conveniently in the stowed position the magazine lies closely alongside the projector.

In a preferred arrangement the magazine is retained in the stowed position by a snap action clip which can be released on application of a sufficient force.

Conveniently the projector and magazine are formed from a high strength polymer plastics material.

According to a further aspect of the invention, there is provided a projector having means for slideably bearing a magazine bearing a plurality of signal cartridges, so that upon sliding of the magazine relative to the projector each cartridge can be brought in turn into a position for firing by the projector, the projector being capable of firing the cartridges one at a time.

According to a still further aspect of the invention, there is provided a magazine bearing a plurality of signal cartridges, and having means for slideable mounting on a projector whereby each cartridge can be brought in turn into a position for firing by the projector.

The invention will now be more particularly described by way of example only, with reference to the accompanying drawings in which, Figure 1 is a pictorial view of a signalling device according to the present invention, when in an operational condition.

Figure 2 is a pictorial view of the signalling device of Figure 1, showing the magazine in a stowed condition.

Figure 3 shows in sectional elevation, the signalling device of Figure 1.

Figure 3a is a sectional part view along the line A-A of Figure 3 as viewed in the direction of the arrows.

Figures 4a, 4b, 4c show sequentially the steps required to introduce a magazine on to the projector and to manoeuvre it into a stowed position.

Figures 5a, 5b, 5c, 5d show sequentially the steps of removing the magazine from a stowed position and manoeuvring the magazine into an operational position.

Figures 6a, 6b, 6c are a pictorial view, a sectional plan view, and a sectional elevation respectively, of part of the magazine and projector, showing the method of location therebetween.

Figure 7shows, partly in section, a side view of another embodiment of magazine suitable for use with the projector shown in Figures 1 to 6.

Figure 8 is a sectional end view of the magazine of Figure 7, and Figure 9 is a plan view of the magazine of Figures 7 and 8.

Referring first to Figures 1 to 6, the signalling device as illustrated comprises a hand held projector 1 with a generallyT-shaped slot 2, formed along the length of one longitudinal end face, the slot 2 including a downwardly extending groove 3 constituting the leg of the T and a pair of laterally extending recesses 4 constituting the arms of the T.

A magazine 5 housing six signal cartridges 6 is slideably constrained in the slot 2 by means of a complementary T-shaped flange 7 projecting from the magazine. One side of the groove 3 is chamfered as shown at 8 in Figure 3a. The flange 7 on the magazine has a complementary chamfer so thatthe magazine may be inserted in one orientation only.

The projector 1 is further provided with a slot 30 (Figures 4, 5) continuous with the slot 2 and extending substantially the length of one longitudnal face of the projector. The slot 30 is of a width sufficient to receive the flange 7 on the magazine.

Both the projector 1 and the magazine 5 are formed from a high strengh polymer plastics material.

At one end of the flange 7 there are provided a pair of pivot lugs 9. The recesses 4 provide sufficient clearance for the lugs 9 to slide therein, but an end stop 10 (Figure 6b) is provided which the lugs cannot pass.

The end stop 10 together with the end portions of the recess 4 define a pair of pivot bearings in which the lugs 9 can engage thus limiting the travel of the magazine in one direction. The arrangement is such that when the lugs are so engaged the flange 7 clears the slot 2 (Figure 6c) so that the magazine may pivot relative to the projector about the axis of the lugs 9 into an inoperative or stowed position in which the magazine 5 lies closely alongside the projector 1 with the flange 7 accommodated by the slot 30 in the side of the projector.

At the base of the projector is a platform 11 having a resilient enlarged end portion 12forming a snap action clip which receives and positively retains the magazine when it is in the stowed position. The end of the magazine remote from the lugs 9 is recessed as shown at 13 so as to be of complementary shape to the platform 11 and the end portion 12.

The body of the projector serves the function of a handle in use of the device and is provided with depressions 15 for the fingers of an operator holding the projector. The projector is also provided with a trigger 16 which may be easily manipulated by the thumb of the operator whose fingers are engaged in the depressions 15. The trigger 16 is mounted flush with the surface of the projector to guard against accidental firing, The firing mechanism of the signalling device is shown in Figure 3 and comprises a striker pin 17 borne by a plunger 18 reciprocable in a bore 19 within the projector 1. The plunger is biased upwardly towards the magazine (ie, when in its operational positon) by a spring 20 compressed between the plunger18and afixed insert 21 within the bore 19.

Attached to the plunger 18 is a rod 22 which extends from the lower end of the bore 19 and a lanyard 23 is threaded through the lower end of the rod.

The trigger 16 is pivotably mounted on a pin 24 and has a nose portion 25 which is urged into the bore 19 underthe biasing action of a trigger spring 26 which can be opposed by an operator depressing the trigger. The plunger 18 is provided with two detent portions constituted by an annular groove 27 and a shoulder 35 with which the nose portion 25 is engageable to restrain movement of the plunger.

The projector 1 is provided with a spring-loaded captive ball 28 which can co-operate with each of six indents 29 in the magazine so as correctly to locate a respective signal cartridge relative to the striker pin 17 prior to firing.

The magazine 5 comprises a rigid body having formed therein six shaped bores in each of which there is received a signal cartridge 6. Each signal cartridge comprises a flare blank 30 located in the base of the magazine and a flare case 31 sealed in the magazine by means of a dish seai 32. The flare case 31 contains a gunpowder priming 33 located such that it is adjacent to the flare blank and above the priming 33, a 'star' composition 34.

A fresh magazine is fitted to the projector as shown in Figures 4a to c. As shown in Figure 4a a magazine must be aligned with the projector so that the flange 7 at the end remote from the lugs 9 is received in the T-shaped slot 2. The magazine may then be slid to the end of its slideable range (Figure 4b) when the pivot lugs 9 engage the end stop 10 and the magazine may be pivoted into a stowed position (Figure 4c).

It will be appreciated that the operational procedure involved in discharging a signal is considerably simpler than is the previously mentioned devices. As shown diagrammatically in Figures 5a to d, preparatory to firing a signal it is necessary to unclip the magazine from the platform 11, pivot it away from the stowed position about the lugs 9 (Figure 5a) and slide the magazine along until the required cartridge is in the firing position (Figure 5b). The springloaded captive ball 28 and the indents 29 on the magazine ensure that the cartridge is located correctly above the striker pin.

To 'cock' the projector the lanyard 23 must be pulled (Figure 5c) moving the rod 22 against the biasing force of the spring 20, so that the plunger 18 is withdrawn until the trigger nose portion 25 engages the shoulder. This is the condition shown in Figure 3.

To fire a signal cartridge, pressure is applied to the trigger 16 to overcome the biasing force of the trigger spring 26 and pivotthe trigger about pin 24 so that the nose portion is withdrawn from the bore 19 and the plunger is free to move rapidly along the bore under the action of the spring 20. The striker pin 17 will then strike and fire the flare blank 30 which propels the cartridge onto the air and ignites gunpowder priming 33. The priming 33 burns until such time as the cartridge has attained a considerable height before igniting the 'star' composition 34 which burns with a bright colour. The 'star' composition is such that the 'star' will burn for a considerable time but will always burn out before reaching the ground. 'Stars' of red, green, yellow or white are envisaged as likely colours.

After the pin has struck the flare blank, and upon release of the trigger, the nose portion 25 can enter the groove 27 to restrain the plunger 18 against further axial movement in its bore.

If it is desired to fire a further signal the magazine can be slid to a position where another live cartridge is in the firing position (Figure 5d) ie above the striker pin 17. The engagement of the nose portion 25 in the groove 27 prevents accidental movement of the plunger 18 which could result in unintentional firing. The provision of a separate safety catch is rendered unnecessary.

An alternative embodiment of magazine for use in the invention is shown if Figures 7 to 9. As with the previously-described embodiment of Figures 1 to 6, the magazine 5 is provided with a T-shaped flange 7, at one end of which are a pair of pivot lugs 9. The magazine comprises a base portion 42 integral with a vertical wall 40 which defines the perimeter of the magazine on four sides to form an open topped chamber 41. Raised up from the base portion 42 are six spigots 43 each with a central bore 44 in the lower part of which is fitted a flare blank 30. A signal cartridge 6 in the form of a flare case 31 is located on each spigot 43 by means of an extended skirt portion 45 which is shaped so as snugly to fit over the spigot 43. The flare case 31 contains a gunpowder priming 33 above which is a 'star' composition 34.

The procedure for firing a signal cartridge is similar to that previously described. When the trigger 16 is pressed the trigger mechanism operates to allow the striker pin 17 to strike and fire the flare blank 30. The hot propellant gas produced by the flare blank passes along the base 44 at the centre of the spigot to propel the signal cartridge into the air and to ignite the priming 33. The skirt 45 forms a sliding seal against the spigot 43 to contain the propellant gases on firing. When the cartridge has gained sufficient height to be visible, the 'star' composition 34 is ignited by the priming and burns with a bright colour.

Claims (28)

1. A pyrotechnic signalling device comprising a magazine bearing a plurality of signal cartridges, and a projectorforfiring the cartridges one at a time, wherein in an operational condition the magazine is borne slideably on the projector so that upon sliding of the magazine relative to the projector each cartridge can be brought in turn into a position for firing by the projector.

2. A pyrotechnic signalling device according to claim 1 wherein the projector and the magazine are provided one with a slot and the other with a complementary projecting portion, the projecting portion being slideable in the slot and captive therein when in the operational condition.

3. A pyrotechnic signalling device according to claim 1 or claim 2 wherein the projector and the magazine are provided one with lugs extending laterally one on each side of the axis of sliding and the other with a complementary pair of pivot bearings in which the lugs are engageable whereby the magazine can pivot about the common axis of the lugs in their respective pivot bearings between operatinal and stowed positions.

4. A pyrotechnic signalling device according to claims 2 and 3 wherein the lugs are slideable in the slot and the pivot bearings are continuous with the slot and defined by one end stop therein which the lugs cannot pass.

5. A pyrotechnic signalling device according to claim 3 or claim 4 wherein the lugs engage their respective pivot bearings when the magazine reaches a limit of sliding movement in one direction.

6. A pyrotechnic signalling device according to claim 5 wherein the magazine can be detached from th projector by sliding in an opposite direction.

7. A pyrotechnic signalling device according to any preceding claim wherein the magazine lies closely alongside the projector when in a stowed position.

8. A pyrotechnic signalling device according to claim 7 wherein the magazine is retained in the stowed position by a snap action clip which can be released on application of a sufficient force.

9. A pyrotechnic signalling device according to any preceding claim wherein the projector is formed from a high strength polymer plastics material.

10. A pyrotechnic signalling device according to any preceding claim wherein the magazine is formed from a high strength polymer plastics material.

11. A pyrotechnic signalling device according to any preceding claim wherein means are provided positively to locate a signal cartridge relative to the projector prior to firing.

12. A pyrotechnic signalling device according to claim 11 wherein the means for locating a signal cartridge relative to the projector comprises a spring-loaded captive ball which can co-operate with any one of plurality of indents in the magazine so as positively to locate a respective signal cartridge.

13. A pyrotechnic signalling device substantially as hereinbefore described with reference to Figures 1 to 6 of the accompanying drawings.

14. A pyrotechnic signalling device as claimed in any one of claims 1 to 12 and including a magazine substantially as hereinbefore described with reference to Figures 7 to 9 of the accompanying drawings.

15. A projector for use in a pyrotechnic signalling device according to claim 1 having means for slideably bearing a magazine bearing a plurality of signal cartridges, so that upon sliding of the magazine relative to the projector each cartridge can be brought in turn into a position for firing by the projector, the projector being capable of firing the cartridges one at a time.

16. A projector according to claim 15 wherein the means for slideably bearing a magazine comprises a slot adopted to receive a complementary projecting portion on the magazine.

17. A projector according to claim 15 or claim 16 including a pair of pivot bearings with which a pair of lugs on the magazine are engageable to pivot the magazine between operational and stowed positions.

18. A projector according to claim 16 and 17 wherein the pivot bearings are continuous with the slot and defined by an end stop which the lugs on the magazine cannot pass.

19. A projector substantially as herein before described and with reference to Figures 1 to 6 of the accompanying drawings.

20. A magazine adapted for use as part of a pyrotechnic signalling device according to claim 1, the magazine having means for slideable mounting on a projector whereby each cartridge can be brought in turn into a position forfiring by the projector.

21. A magazine according to claim 20 and bearing a plurality of signal cartridges.

22. A magazine according to claim 20 or claim 21 wherein the magazine is provided with a projecting portion which is slideable in a complementary slot in the projector.

23. A magazine according to any of claims 20 to 22 wherein the magazine is provided with laterally extending lugs adapted to engage a pair of pivot bearings on the projector to pivot the magazine between operational and stowed positions.

24. A magazine according to any of claims 20 to 23 wherein each signal cartridge comprises a flare blank, an area of which is exposed for firing by the projector, and a flare case containing a gunpowder charge and a pyrotechnic signal composition.

25. A magazine according to claim 24 wherein each flare case is frictionally retained in a chamber in the magazine.

26. A magazine according to claim 24 provided with a plurality of spigots and wherein each flare case is provided with a skirt portion which fits snugly over a respective spigot to locate the flare thereon.

27. A magazine according to claim 26 wherein each spigot has a bore therethrough opening within the skirt portion, said flare blank being housed within said bore.

28. A magazine substantially as hereinbefore described and with reference to Figures 7 to 9 of the accompanying drawings.