US1842369A - Gas liberating charge - Google Patents

Description

Jan. 19, 1932. A owY 1,842,369

GAS LIBERATING CHARGE Filed May 24. 1929 Patented Jan. 19, 1932 UNITED STATES PATENT-f OFFICE! ALEXANDER LOW'Y, OF PITTSBURGH, PENNSYLVANIA, ASSZlYG-NOR TO FEDERAL LABORA- TORIES, IN 0., OEIPITTSBURGH, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA V ens mnnnn'rme cannon Application filed May 24, 1929. Serial No. 365,592.

My invention relates to dispersing irritatlng substances, and more particularly to con- I tainers and container charges for-liberatmg gas of an incapacitating character.

V In devices for liberating incapacitating gasit has heretofore been customary to provide acontainer in which a charge of powder is ignited by a cap. The burning of the powder generates gas which discharges a body of small particles of a chemical compound which, when released to air either with or without the. heat incident to the burning of the powder charge, is transferred to a smog, colloidal and/or gaseous state. a The gas serves to'incapacitate a person within the zone of discharge of the contents of the container.

A number of types of devices for discharging such containers are in use. These devices take the form of pistols, policemens maces,

fountain pens, pencils, bombs, and the like.

Some of the containers when in the, form of cartridges have the general shape of a shot gun shell and are usually made in sizes cor responding to standard sizes of bullets so that the cartridges can be used in standard fire arm's, if desired.

When containers as heretofore constructed have been discharged, the chemical com-, pounds in a finely divided state have been discharged as a spray of v,liberatedgas and small particles of the charge. As the effectiveness of the charge depends to a consid- 'erablo extent upon its remaining in the air, where the particles can be converted intoa gaseous state, the presence of large particles of the charge lowers the efficiency of the discharged products. The large particles ofi'er less exposed surface area ,per unit of weight to the atmosphere than do'fine particles or thin films. The large particles do not remain suspended in the air as long as the small particles since the larger particles fall more rapidly than do the smaller particles which tend to float in the air. The particles of the charges also tend to form aggregates and cohere, thereby producing larger particles or lumps, with the resultant disadvantages of less surface area per unit of 50 weight and-a higher'settling-speed. -As a" result of such conditions considerable more of the chargehas been placed in the containers than is ultimately converted into gas.

Chloroacetophenone is a common chemical used in such containers and the commerical product is somewhat oily in its nature and tends to cohere.

The life of such containers and charges as heretofore constructed has been limited to rather definite periods of time by reason of the deterioration of the gas producing charge, as the result of chemical deterioration occasioned by chemical reactions between the various ingredients in the container. This is true where chloroacetophenone is used as a gas liberating charge.

I provide a container in which a barrier or wad having a cooperating coating or film, impervious to the vapors liberated by the gas liberating charge, is interposed between the propelling powder and the charge. The presence of the impervious coating prevents the circulation of gases from the charge into contact with the propelling powder, thereby preserving the efl'ective life of the gas libcrating charge over periods of a considerable number of years. Where chloroaetophenone is used, a nitrocellulose coating may be employed. It is to be understood, however, A

that the invention contemplates the use of charges other than chloroacetophenone. Such charges may be of stenchatory, lachrymatory, like characteristics as desired.

For preventingthe formation of aggresuring a better floating of the particles of the material inthe air, the chemical compounds of the gas liberating charge are associated with an inert substance. The: inert substance is of a light flufl'y nature with considerable surface area, such that each particle tends to float in the air and retain its individual shape sternutatory, fumigatory and the gates ofthe discharged material and for inwithout cohering into an aggregate. By

coating the particles of inert matter with thin films of the chemical compound, greater surface areas per unit weight of the chemical charge-is obtained. This produces a saving in the amount of'the incapacitating chemical compounds required with greater efficiency.

The single figure of the accompanying drawing illustrates a present preferred. embodiment of the invention.

Referring to the drawing, a container illustrated in the form of a cartridge 2 having a base 3 of metal, such as brass, is provided with a firing cap 4. The cap 4 is ignited by a firing pin mounted in the weapon in which the cartridge is inserted. The cap 4 ignites a body 5 of inflammableymaterial, such as black or smokeless powder, for developing a pressure and heat to discharge the contents of the cartridge after the ignition of the ca 4.

The inflammable charge 5 is-covered by a barrier or wad 6 which separates it from a charge 7 of a chemical mixture which, upon being discharged into the air, is an irritant and is converted into fine particles of the desired irritating characteristics. The compounds frequently used in such cartridges release an incapacitating gas which may be of any one of a number of types, such as stenchatory, lachrymatory, sternutatory or fumigatory. A chemical compound frequently used for such purposes is chloroacetophenone.

For reventing the deteriorationpf the propelling charge 5 by infiltration of gases between the charge 7 and the inflammable charge 5, the wad 6 is provided with a coating or film 8, preferably placed on top of the wad. The material of the coating 8 is impervious to the gases liberated by the' charge 7. Suitable impervious material for the coating 8 is obtained from films of cellulose derivative type lacquers or gum varnishes, or both, containing cellulose derivatives.

Where chloroacetophenone is used in combination with either black or smokeless powder, a slow deterioration of the chemicals results by mutual reactions of the ingredients. By providing an impervious coating 8, such circulation or infiltration is prevented and the chloroacetophenone and powder used for propelling purposes are kept in eflective condition over long periods of time. The top of the cartridge is closed by a wad 9*having a water-proof coating 10. The edge 11 of the cartridge 2 is spun over to rest on top of the wad 9. I

- For preventing the cohesion of aggregates of the discharged particles of. thecharge 7,

the incapacitating chemicals are in a thin film associated with an inert material, in a finely subdivided state, and to which the chemical particles adhere. The inert material may be one of any one of a number of such materials, each of which is light, fiufl'y and capable of floating in the air for considerable periods of time. By having the fine coating or film of the incapacitating chemical compound disposed over the surfaces of the inert material, the exposed surfaces of the chemical compound per unit of weight is greater than is the case where the particles of the chemical salts cohere and form aggregates. This results in a material saving in the amounts of chemicals used as a more thorough vaporization of the chemicals is obtained with greater efficiency. The presence of the finely divided inert material, which does not go into a gaseous state, also adds to the irritating eflect of the discharged material as the fine particles produce an irritating efiect upon the eyes, nose and throat.

There are a number of inert substances suitable for such purposes, such as finely, pulverized celite, silica, a hydrate of silicon mined in Colorado; silica el powders; bentonite, a geological colloidal clay; finely ground pumice; finely ground China clay; precipitated chalk; asbestine, a ground asbestos; kieselguhr, etc. It is to be understood, however, that the invention contemplates the use of inertmaterials other than those just enumerated.

For producing a film of the incapacitating chemical materials with the particles of inert material, the chemicals may be dissolved in solvents and then mixed wlth the inert partieles, after which the solvents are evaporated and thereby deposit a coatin ofthe chemical material on the particles 0 inert material.

In the case of chloroacetophenone, it may be dissolved in carbon tetrachloride or benzol and deposited on an inert material.

Where it is desired to associate the incapacitating chemical material with the inert material mechanically, the two may be ground together.

While I have shown and described the present preferred embodiment of the invention, it is to be understood that it may be otherwise embodied and practiced within the spirit of the invention and the scope of the appended claims.

I claim:

1. A charge for conveying and distributing irritating gas when expelled by force from a container, comprising a confined mass of detached particles of finely divided solid earthy material said particles being light and capable of floating in air for a considerable time, said particles being coated with films of 3. A charge for conveying and distributing irritating gas when expelled by force from a container, comprising a confined mam of detached particles of finely dividedsiliceous material said particles being light and capable of floating in air for a considerable time, said particles being coated with films of an irritant which is solid at ordinary temperatures.

4. A charge for conveying and distributing irritating gas when expelled by force from a container, comprising a confined mass of detached particles of .finely divided kieselguhr coated with films of chloracetoph'enone.

In testimony my hand.

whereof I have hereunto set LEXANDER LOWY."

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