US1992690A - Safety pyrotechnics - Google Patents

Description

Feb. 26, 1935.

J. B. DECKER SAFETY PYROTECHNICS Filed Jan. y16, 1954 f www@ Patented Feb. 2e, 1935 "fff'fUNlTEDaSTATES Parmi J SAFETY rYnoreonNIos Josef Decker, ElktomMd. y 1 application January 16, 1934, serial No. 706,874 1 11m-aims.` (crime-2 5) 1 This invention relates to pyrotechnics and parv ticularly to safety pyrotechnic devices of the, type adapted to produce either a report, a brilliant flash, ascintillating display, or any combination oftheseeffects. .l 1 1 1 .It is a` general object of thepresent invention to provide a novel and improvedpyrotechnic.

More particularly it` is an object ofthe device to provide a pyrotechnic in -whichlthe initiating explosion `caused by agrelatively small quantityof readily detonated explosive is transmittedsymf l pathetically to the ,main or secondary charge, the

explosion of l which produces report, or thelike. 1 t.

An important feature ofthe-invention consists in `,making the primary or initiatingdischarge result 1 from a small quantity of materialof rela'-` tive11y, high sensitivity, imparting its erect 'as a booster todischarge the mainA orsecondary` explosive ofv relatively greaterquantityand less sensitivity. 1 1 1` u When applied to toy torpedoes," the invention is` of considerable importance since it permitsthe use, ,of the f minimum quantity of the' sensitive explosive material which is discharged by impact," for instancapby the use1of gravel mixed therewith, andldetonates a; large charge of relatively insensitive material so thatgthe possibilitiesof unintentional:v explosion are reducedfto a mini` mum and the danger duringmanufacture is'very materially curtailed'` 1 i A further important feature resides sibility,oi-incorporating thegprimary and second-` aryexplosives within `a single container which caribe of considerablyfless gas-retaining strength than those heretofore used, sinceits essential purpose is mainly to hold the elements assembledz theexplosion resulting from "the detonating orA boosting of the secondary explosive being so vio-- lent and of1 such short durationthat a .highly` resistant gas enclosingcasingis not'essential` to obtain the maximum loudness of 1 report or. dispersionofflash material.- 1 1 f --As another important feature of the invention maybe mentioned the possibilityof totally enclosing the `primary or detonatingexplosive within' a cushioningl layer of the secondarypyro-l technic material, whereby it is protected against shock :or accidental "discharge during v rnar'iufacture,1 shipping, sale,` and handling by the vultimate consumer priortothe very` dei-mite and1 intense shock vresulting from nally throwing the'device against a solid wall, pavement, or the like;

Other important objectsv andfeatures of1 the inventionwill be more apparent to thoseskil1ed l scope of the appended claims.

the essential display,

in the' pos- Y in the art upon aconsideration'of the accompanying `drawing Aand following specification,` wherei'niare disclosed several exemplary embodiments of the invention, with the understanding, however, that other andicorrespondin'g develop-4 ments are possible as'well `as combinations and variations of the disclosed embodiments without departingfrom the spirit of the invention or the In said drawing: l

Figure 1 is a longitudinal central section through a preferred form of toy torpedo constructed according tothepresent invention;

Figure 2 is a schematic showing of the arrangement ofthe explosives therein;

Figure 3 is a furtherschematic showing of another arrangement possible for the explosives;

Figure ll is Va view similar to Figure 1 Aof a fur'- ther embodiment ofthe invention ;1 and Figure' is an additional View, similar to Figure 1,1fof a'still further 1 embodiment of the invention...` 1 1*.1

In the 1'manufactureof 'most pyrotechnic devicesA and. particularly iireworks for amusement, display, andindustrial purposes, it has been the general v1practice to bring about the explosion, detonation, or ignition" by impacts directed onto the Sensitive composition, by'friction, or by liiarne or sparkbrought into Contact with 'a composi` tionwhich explodes as the rate of burning Aincreases. Such `methods of inducing theexplo'- sion have` numerous disadvantages, for in the first place there are very serious limitationsinsoiar as the control of the explosion is concerned and, second-the violenceof theexplosion is very dii'cult to regulate; These two .and other 'faults haveV caused tremendous hazards in the industry; particularly inthe handling and transporting vof the `items which are'thus very unstable and almost beyon'd the control of the workers.

In accordance with *the `present invention, which istb'rcaolly applicable to the' pyrotechnic iield, a novel and unique means ofcreating the main explosion or rapid burning'ismade available by theV utilization of aprinciplerwhich has notV heretofore been used in the pyrotechnic andalliedindustries.r 1 j 1In-`accordance with this invention, a minimum of thel pyrotechnic composition or primary explosive is used,` and its sole purpose is to be initially ignited by concussion, friction, or the' like," to-fact as adetonator or-booster for a pyrotechnic composition which will not, under normal'circumstances, ignite either by concussion or friction, and in' so doing to produce in this secondary explosive a discharge of a more violent nature than that which would result from igniting, it for instance, by fiame or spark.

More specically, the result is produced by a detonating or ulminating agent which assumes the role of a boosting composition which on its initial explosion sets up a pressure Wave of steep front because of its violence, and this wave produces a sympathetic explosion or detcnation of the secondary for main charge fof `:pyrotechnic composition which is Aplaced adacent to, yeit separate from, the primary or detonating composition. By reason of the steep wave front produced by the small charge, the violence .of `the explosion of the secondary charge is 'materially enhanced so that with a lesser totaelmuanuiby (of explosive material a louder report, or brighter flash can be obtained, thereby producing ndt 'only a saving in the quantity of material but ,am iny crease in the safety of the device, a reduction in i-ts 4size and cost, and ,greater'zsaiieizv because of the-less .sensitive nature of `:the total (composition. As previously mentioned, the :inventioniis able dor use 'with a large number -of types of pyrotechnic devices ignited .in @the various manners common iin the art, Abut .for the :sake :of Asimplicity .lit -is shown and ldescribed only in cnn-A nect-ion 'with what is known as :a "toy torpedo of the type adapted tobe thrown against a hard surface to be exploded. Obviously iis not the intent to .limit vthe .claims to this specific embodiment or V.the numerous variations thereof 'but ito have the .invention limited only by the .known prior art.

In Figure 1 whatlis now the preferred form of the invention `is shown. The primary explosive, :fulminating composition, `:or :the Ililre 'is shown at m0 mixed with 1'a suitable :quantity of gravel 11 or similar means .for :ca-using its detonat-ion as the 'result of .fa substan-tialimpact. This mixture is enclosed in Aa 'capsule 'or 'casing 12 preferably formed of two telescoping cups of pressed paper :or the .like which may for .may-not be lcaused to adhere to eachother by the use y'of a suitable adhesive on the telescoping surfaces. i

This inner `capsule and its charge :are placed within :a :quite .similar 'outer `capsule 14, leaving considerable .clearance between the two which is then filled with ra .composition `15 which is Vbest referred Ato .as a secondary pyrotechnic composition. It will be :noted that this secondary vcornposition is in close proximity Ato all sides Yof the capsule :con-taining the initiating charge and completely ysurrounds it. It thus has :two functions, tfirst, to Atake the -intitial explosion yfrom the primary orcdetonating charge and to produce the main report, flash, or whatever the purpose of the Adevice may ibe and, second, to cushion the .more sensitive primary Icharge .and prevent its `unintentionalexplosion 'as the result -of rough handling, l'accidental dropping, jarring -or the :like of lthe device or quantities 'of the devices during packing, shipping, and :so on.

As a speciicexample'it may be stated that the inner-capsulefmaycontain the-customary toy torpedo explosive which comprises a -m-i-Xtur-e of antimony sulphide and potassium chlorate, to whichsulphur maybe added if desired.- rI'he relative quantities of .these ingredients may be va.- ried to suit, since by changing theratio of antimony sulphide to :potassium chlorate, the ldegree of lsensitivity of the explosive composition. can

' be adjusted.

rThe outercapsule rma-y yor may inot have its two parts .glued together, .as vdesired. It -is nlled with a pyrotechnic composition, in every case less sensitive to explosion by impact, friction, or the like than the material contained in the inner capsule. It may be a pyrotechnic composition of any desired type. For instance, for the sole purpose of a loud report, it may be a perchlorate powder, a potassium perchlorate powder, a nitrate or the like, or any of these combined with color and flash-producing materials, such as aluminum dust, srrrertallic lzirconium powder, Vsor '.anyiof the other weld-known `p-yroteoliinic materials. 'Where it is intended to have a flash alone without any substantial report other than that produced by the detonating charge, zirconium powder alone -may lill the space between the two capsules. The `invention is .not concerned with the great variations which may be practiced in the loading of the two "compartments except that the primary charge be'rnore sensitive and ordinarily of less quantity than the secondary or main charge.

' With any :quantity 'limitation on the charges it has been found that 1a very :much louder 'report, 'with .or without an accompanying liash, color., scintillation, yor the ilike,\can be obtained than is possible with the use of the single T4type explosive of the prior tormsof torpedoes.

A torpedo constructed :according tothe present invention has important .advantages -not heretoore recited, :among which may be specifically mentioned lthe lessened :da-nger l.of 'injury to the riser :or to bystanders. Because of the extremely small quantity 'of Ithe -initial explosive material, the Vdetonating agent, i. fe., fthe=gravel,1can be in lesser quantity and of smaller fs'ize so `tlfreit actually ve or .six .pebbles lmay be fsutlicient dor the pur-pose loi .causing the explosion. Likewise the enclosing -icasngs .need not have the 'same gas resisting :properties 4as those rused heretofore in order to obtain .the :same or greater violence 'oi explosion, `so lthalt alloinlall there :are practically no parts of any size, weight, or dangerous chanacteri-stic's to 'sbe v'scatteredby the explosion. The enclosing :capsules .are merely paper I'or thin card# board .not rmich greater in weight than Bristol board zand are lof .a ifairly pul-py 'consistency jand not at all dangerous when 'thrown by Athe -ex-I p'losion.

.Since the :so'le purpose of the :containing casing'is to reifer a .slight .coniinement to the Igases and to' hold the'parts vof the torpedo together dor handling, it is not made at all sturdy 'but is preferably .treated ailter assembly by some v'simple method which 'will .insure the two '-parits remaining Ytogether and which preferably waterproois, at least to .some extent, the whole torpedo'. fSuch a result is readily lobtained by .spraying fthe capsules :in mass lwith an adhesive '-coating, such 4as water-:glass .or silicate :of soda, which can fthen be 'quickly vdried lby the application of a zsmall quantity :of :an absorbent dust or powdersuch as wood flour for the like.1previously colored to ir'npart aidesirable appear-ance to the torpedo. the parts of the main capsule .are securedtogetherby glue v'or other adhesive von assembly, the final waterproofing vand icolor'ing -o'f the torpedo can be donev by 'treatment with :a -colored paint containing Aa heavy pigmentwhich ,may -produce la slight iayer., as shown at 16, :around the capsule.` If the treatment of the exterior .of `the capsule is done while `a :quantity :of #chem is being shaken on ya `vibrating tray, all surfaces will be exposed in a short time :and .the treatment can be applied with a commercial `spray gun.

Another possibility for .encasi-ng the capsule,

coloringzit, and causing the adhesion Aof the itwoparts to each other may be producedbycoating the capsule with casein glue4 in `any desired manner, as by dipping; brushing, spraying-or the like,

explosive is totally encased within the secondary explosive and `thus cushioned from impact, but having a large areaexposed to the explosive wave from the primary explosive.

Figure 3 shows a variation of the arrangementY of Figure 2 in which the secondary explosive is on the interior and the primary explosive on the exterior,giving the same area of exposure of one to the other but placing the primary explosive where it is more readily ignitable where this may be desirable, as, for instance, inrailway torpedoes or the` like. l l

Figure 4 shows a further variation in crosssectionalform, in which both explosivesare arranged in a single enclosing casing in the form of an open-,ended paper cup 20 with the primary explosive and its mixture of gravel in the bottom, as shown at21, and separated by a suitable septum 22 from the secondary explosive 23 placed 'in a thicker layer above the septum. Finally a seal or closure 24 of any desired type is applied to insure the retention of the charge in the cup. The exterior ofthe cup may or may not be treated in themanners described in connection with Figure 1.

A further form of torpedo is shown in Figure 5 which has certain advantages in manufacture. Here the primary explosive 30 is enclosed in a capsule 31 formed of two telescoping paper cups, as described in connection withFigure `1. Included with it is the charge of gravel. The secondary explosive 32 is enclosed in a substantially identical paper cup 33 although the relative heights of these cups may be varied in accordance with the desired ratioof the two explosives, but preferably their diameters are substantially the same. These two capsules are then assembled in any desired relation in a third cup or capsule 35 which may comprise an open-ended tube with suitable plugs or sealing material at the two ends or, as shown, a closed bottom paper cup provided with a sealer 36 at the top'which closely confines the two capsules to prevent rattling. As in the case of Figure 4, this form provides a substantial area of exposure of one explosive to the other for satisfactory detonation` or boosting after the initial explosion of the primary charge.

Various forms of the torpedo diiTerent from those already described are, of course, possible to devise, and other types of pyrotechnics may be constructed, takingadvantage of the present in- Y vention.v The main feature of the invention, however, is not in the specific embodiments but in the utilization of the principle of a small quantity of relatively sensitive explosive, adapted to be detonated by any desired method, arranged in close proximity to a much larger quantity of less Y sensitive pyrotechnical material adapted to be ignited only by detonation from the primary explosive.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is:

1. In a toy torpedo, in combination, an outer casing of substantially gas-tight construction, a primary explosive in said casing, means in the casing to abrade and so ignite said explosive only when the torpedo is violently shocked, a secondary explosive in saidcasing, and a wall separating said explosives in such a mannerthat the second can only be'detonated bythe first.

J2. *In a torpedo of the type described, in combination,?a` closed casing, a small quantity of sensitive explosive and percussion igniting means therefor enclosed in said casing, and meansenclosing a larger quantity of less sensitive explosive in close proximity to the first explosive for detonation therefrom.

`3. In a pyrotechnic device adapted to be ignited on impact, in combination, a small charge of fulminating explosive, percussive means to ignite the same on impact, a closing casing for said charge and means, a second casing loosely surrounding the first and a charge of pyrotechnic composition of low sensitivity between the two` confining said charge and means, a large casing of gas-tight material loosely surrounding said envelope and pyrotechnic composition lling all the space between the casing and envelope and cushioning the explosive on all sides.

5. In a torpedo of the type described, in com` bination, at least two explosives, one of small quantity, high sensitivity and, low power, another of larger quantity, low sensitivity and great violence, means associated therewith to ignite the first explosive by impact and means so conning the two explosives separately that the second may only be detonated in sympathy with the first.

6. In a torpedo of the type described, in combination, at least two explosives, one of small quantity, high sensitivity and low power, an-

other of larger quantity, low sensitivity and of great pyrotechnic value, means associated with the first explosive to ignite the same upon impact, means enclosing the rst explosive andv said means, a container for the second explosive, and means positioning it so that the second explosive will be detonated by the rst explosive.

7L In a torpedo of the type described, in combination, explosive sensitive enough to be ignited by impact, abrasive means mixed with saidexplosive, an envelope for said mixture, a larger -quantity of a less sensitive explosive completely surrounding said envelope and arranged to be ignited only by detonation, and a substantially gas-tight casing for the whole assembly.

8. In a torpedo of the type described, in combination, explosive sensitive enough to be ignited by impact, gravel mixed with said explosive, a tight'envelope for said mixture, a quantityV of pyrotechnic composition of low sensitivity against a wall of said envelope andadapted to be ignited only by detonation and a gas-tightcasing enclosing the envelope and composition.

9. In a toy torpedo, in combination, an envelope formed of telescoping paper cups, a sensi- Vtive explosive and gravel therein, a second and larger envelope of telescoping paper cups loosely surrounding the rst envelope, a charge of pyrotechnic composition filling the space between the two envelopes and means to secure the parts of the second envelope together,

10. A toy torpedo of the type described and including a powdered primary explosive, gravel intimately mixed therewith to ignite the same on impact, a secondary'explosive of great violence close to the primary explosive, a flame-tightpartitionseparating said explosive, and a casing for both explosives of only sufcient strength to conne them during manufacture and shipment. o 11;In a torpedo adapted to be exploded by impact, in combination,- a small charge of sensitive explosive composition, abrasive means to ignite thesame on impact, 'a charge of pyrotechnicfoomposition in greater quantity ythan said sensitive explosive, llametight means separating the explosive and pyrotechnic compositions wherebythe second is exploded only by sympathy from the rst, and a closed casing around all of said elements. vJOSEF B. DECKER..

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