US2269582A - Signal flare - Google Patents

Description

Jan., )13, 194,2. J. B. DECKER S IGNAL FLARE Filed March 11, 1958 @Moana/n.

Patented Jan. 13, 1942 grate stares alargar esta SIGNAL FLARE .lcsef B. Decker, Elkton, Md., assignor to Triumph Explosives, Inc., a corporation cf Maryland Application March 11, 1938, Serial No. 195,403

1l Claims.

signalling it is only essential to ensure that the projectile fully clears the aircraft before the signal is ignited.

The cartridge of the present invention comprises what might be termed fixed ammunition for it includes as an assembly a cartridge v case, a projectile and a propelling charge. The cartridge case is adapted to be received in and held by a suitable fire arm such as a signal pistol which preferably has a short barrel arranged for muzzle loading. The projectile carries suitable signal means such as a nare, smoke shell or the like, adapted to be suspended, if desired, from a parachute. The parachute and are are loaded into the projectile along with an expelling charge which is ignited from a delay fuse and serves to eject the nare and its parachute and light the former. The delay fuse is ignited when the propelling charge is fired.

The present invention is concerned primarily with these features of the fixed ammunition which relate to the propelling of the cartridge or projectile from the cartridge case and gun, and it is therefore a general object of the present invention to provide novel and improved xed ammunition.

More particularly it is an object .of the present invention to provide xed ammunition in which the propelling charge is carried by the projectile.

An important feature of the invention resides in the arrangement of the propelling charge to be carried by the rear end of the portion of the projectile which is received in the cartridge case, together with means to direct the flash of the percussion cap, in the cartridge case, into this charge for igniting the same.

Another important feature of the invention resides in a construction of cartridge case and telescoping projectile portion which permits a reduction of substantially 50% in the quantity of propelling charge without reducing the range of the projectile.

A further important feature of the invention resides in the arrangement of the propelling charge, the delay fuse and the'percussion cap, whereby the llame or ash originated by the latter ignites the two former substantially simultaneously.

A still further important feature of the invention resides in the novel construction of thecase portion of the projectile whereby it can be assembled from a minimum number of light-weight parts.

Other and further features and objects of the invention will be more apparent to those skilled` in the art upon a consideration of the accompanying drawing and following specification wherein is disclosed a single exemplary embodi-v ment of the invention with the understanding that such changes may be made therein as fall within the scope of the appended claims without departing from the spirit of the invention.

in said drawing, the single figure is a central longitudinal section through a signal cartridge constructed according to the presentvinvention.Y

The early forms of signal cartridges were developed prior to and during the World War from large size shotgun vshells or variations thereof adapted to be fired from breach loading arms of which the so-called Very pistol is the bestv known example. As these cartridges became larger in order to ,accommodate more powerful signals and parachutes for supporting them, it became desirable to make the projectile cases as well as the cartridge cases from metal to insure strength and water-tightness, and for the sake of lightness aluminum has. become the preferred metal. As the projectiles became larger and heavier, the recoil became undesirably powerful so that difficulty has been experienced in hold ing the pistol Without shock or injury to the hand, especially where the same is projected above the cowling of an open cockpit of a high speed airplane.

For some purposes the projectiles are now as large as two and one-half inches in diameter, although the cartridge case is usually of one and one-half inch diameter to t in a standardized pistol. With this combination, the cartridge case must of necessity be short for it alone is received in the barrel of the pistol. Two inches is about the maximum length of the cartridge case and beyond thatI the larger diameter of the projectile begins. The projectile has a reduced rear portion which is received in the cartridge case to be acted on by the expanding gases of the propelling charge. Because of the short length of the cartridge case and gun barrel and the large size and weight of the projectile, it has been necessary to provide a relatively heavy charge of explosive to obtain a sufficient range for the projectile and this has in part been responsible for the considerable recoil.

Two factors in the present construction serve to reduce the recoil. They are rst, the cylindrical bore of the cartridge case and the close t of the reduced portion of the projectile therein throughout its length eliminating any substantial loss of gas pressure and providing excellent obturation and, second, the arrangement of the propelling charge in a rearwardly extending recess in the base of the projectile, rather than in the cartridge case, where it acts more directly on the projectile. It has been found that a reduction of substantially 50% in the weight of the propelling charge can be effected in the construction shown without reducing the range of the projectile. 't

In the drawing there is depicted a large diameter projectile with a reduced diameter cartridge case, although it is obvious that the device can be constructed with the projectile of substantially the same diameter throughout its length, which diameter is such as to provide a close t within the standard size cartridge case.

The cartridge case I8 is of more or less conventional form having the cylindrical outer wall II of a diameter to be snugly received in the bore of the pistol barrel and having the thickened base I2 provided with a circumferential groove I3 for the reception of a locking lug or the like to hold the case in the bore of the pistol. A conventional percussion cap I4 is pressed into the base and a continuation I5 of the opening into which it is received provides a iiash port to the interior of the case. The inner wall cartridge case is truly cylindrical throughout its length. The parts described complete the cartridge case in every respect and it receives of itself no charge of explosive.

The projectile casing may well be made as a unitary structure, but as shown, it is formed of three major parts, the iirst the tube I8 of the desired length and diameter to provide a loading chamber to receive the flare or other pyrotechnic signal device i9 and the accompanying parachute 28 which is attached thereto by the usual lanyards and cable, not shown. It will be understood that the charge in the tube I8 may be varied as desired without departing from the spirit of the invention. The tube wall is quite w thin for the sake of lightness since it is subject to no considerable stresses. Its lower end is ilanged inwardly as at 2| and against the inner shoulder formed by this iiange is fitted the second member, a substantially ilat circular metal head 22 which has at the center of its upper face the recess or pocket 23 for the reception of the expelling charge 24 which serves to ignite the ilare and drive it and its parachute from the projectile casing after a predetermined interval following the iiring of the percussion cap as will be later explained.

The head 22 has projecting integrally from its rear face a tubular portion or stem 25 exteriorly threaded at its lower end as at 25 to receive thereover the threaded partition 21 of the third member of the casing. This member includes a sleeve or tube 28 constituting the reduced portion of the projectile which is received in the bore of the cartridge case. The cylindrical external wall 29 of this tube 28 has a close lit in the bore of the cartridge case which is such as to retain the parts assembled as fixed ammunition. The sleeve 28 has substantially the same length as the interior bore of the cartridge case I5 of the so that its lower end 38 rests on the at bottom thereof. Its upper end 32 bears against the annular washer 33 which engages the outer face of the iiange 2l and tightly clamps the same against the head 22 when the part 2S is screwed onto the stem 25. The bore of this washer as shown at 34 is such as to engage the filleted portion 35, at the junction of the head 22 and the stem 25, to center the same.

The assembly of the shell I8, the head 22 with its stem 25 and the sleeve 28 with its washer completes the metal part of the projectile and provides the annular chamber 35 between the stem and the inner wall of the sleeve 28. This lightens the construction and may have a further use as will be later described. Beneath the partition 21 is the annular recess 38 the size of whichY is properly determined to receive the desired propelling charge which is packed into the space between the extension 39 of the tube 28 and the lower end of the stem. This end of the stem is cut off squarely to iit tightly against the bottom of the cartridge case. A suitable charge of explosive 48 is arranged in the recess 38 and retained in place by a cover or washer 4I of felt or the like, which may be pressed into position or threaded over the stem. It will be noted that the rear portion of the projectile completely lls the cartridge case.

The bore 42 of the stem 25 is in alignment with the flash port I5 for the percussion cap and a lateral passage or passages 43 through the wall of this tube connect its central bore 42 with the recess 38 so that the iiame or sparks originated by the percussion cap is directed into the propelling charge to ignite the same.

Forwardly of these lateral passages 43 the bore of the tube is so designed as to receive any suitable means to ignite the expelling charge after a predetermined interval, for instance the delay fuse, generally indicated by the reference character 45. This is a commercial article :in the form of a metal tube open at both ends and containing a charge of compressed pulverized powder. The iineness of the powder and the degree of compression determine the length of burning very accurately and the type of delay fuse selected is that desired for the purpose to which the projectile is to be put. The exposed end 46 of the delay powder is in direct alignment with the flash port I5 so that the delay material is ignited simultaneously with the ignition of the propelling charge. Should the propelling charge fail to ignite from the flash of the percussion cap, the burning of the delay will produce sufficient flame to insure its ignition.

The ash from the upper end of the delay powder train which extends close to the expelling charge 24 ignites the same aiter the projectile has been inthe air a suflicient time for the delay material to burn through,

It may be found desirable to reduce the shock of the explosion of the propelling charge by permitting its gases to expand through the lateral bore 5I leading from the bore 42 into the chamber 38. This may serve to reduce the shock oi recoil. A further reduction in recoil can be obtained by using smokeless powder as the propelling charge. It is well-known that this burns slower with less recoil, but cannot be used unless good obturation is insured as by the above mentioned construction. This powder also is safer and since it produces no smoke or flash does not reveal the presence of the plane from which the flare has been red.

This invention has been described for the sake of simplicity as applied to a signal cartridge in which the projectile carries a ilare candle and parachute, and in which the cartridge case is of a suitable size to be accommodated in the standard signal pistol, but it will .be appreciated that a number of the features of the invention will be of value for other forms of ammunition, and it is not intended that the vclaims be construed except in this light.

A number of advantages accrue from the construction just described. Because of the close t of the reduced rear end of the projectile within the full length of the cylindrical bore of the cartridge case, full use is made of the expanding gases from the propelling charge. In spite oi' the short time which elapses before the projectile leaves the cartridge case and the pistol barrel, suicient velocity is imparted to it to carry the same to the desired distance. This full use of the propellant permits a reduction in its quantity and hence a material lessening of the shock of recoil,

By having the propelling charge loaded into the recess in the rear end of the projectile, it will be apparent that all of the loading can be done in one of the two major parts of the cartridge and manufacturing operations thereby simplified. This position of the propellant permits its full energy to be directed `against the projectile, fur- 3,.,

ther reducing the recoil.

In previous constructions the delay fuse has been ignited from the flame of the propelling charge and inaccurate timing has resulted. In

the present construction the delay fuse and the propelling charge are ignited simultaneously from the single flash of the percussion cap, thus insuring positive timing and definite ignition of the fuse train from a source primarily intended for that purpose.

The new construction is exceedingly simple and cheap. The loading is reduced to a minimum number of operations, all of which take place in the open, and the shell is so designed that it can readily be inspected and reloaded if desired after the expiration of a time limit sometimes placed on such devices.

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

l. Fixed ammunition for large-bore signal pistols comprising in combination, a short cartridge case having a straight bore, a percussion cap in the base of said casey a projectile having a portion adapted to closely lit the walls of the said bore throughout substantially its whole length, an expelling charge in said projectile, a recess in and open to the rear end of said portion, a charge of explosive in said recess to propel the projectile, a rear cover for said propelling charge, a tube extending through said charge and cover and having its end engaging the base of the shell with its bore in alignment with the percussion cap flash opening, a lateral passage in the wall of said tube to conduct the cap llame to the said propelling charge and a delay fuse in said tube forwardly of said passage and adapted to be ignited by said cap flame, said fuse being adapted to ignite said expelling charge.

2'. Fixed ammunition for signalling comprislng in combination, a cartridge case having a straight bore, a percussion cap in the base thereof, a projectile extending closely into said bore for substantially the full length thereof, a propelling charge in the base of said projectile, an

of, an annular recess in the base of said portion,

a propelling charge filling said recess, a loosetting rear-cover for the recess, a tube extending through the charge and cover, abutting the bottom of the case and having a bore to receive the flame of the percussion cap, and a lateral opening in the tube Wall extending to the said recess.

4. A signalling cartridge for short-barrel, large-bore fire-arms comprising a cylindrically bored cartridge case as long as the barrel of the i, arm, a percussion cap in the base of said case, a

projectile several times longer than the said case and having a cylindrical portion to closely t said case for the full length of the bore thereof, an annular recess in the base of said portion, a

propelling charge lling said recess, a loose-t-v ting rear cover for the recess. a tube extending through the charge and core, abutting the bottom of the case and having a bore to receive the llame of the percussion cap, a lateral opening in the tube wall extending to the said recess and a delay fuse in the forward portion of said tube having one end directly exposed to the said flame.

5. A cartridge for fire-arms comprising in combination, a cartridge case having a cylindrical bore for its full length, a percussion cap in the base of said case, a projectile having a part closely and completely lling the whole bore of said case, a propelling charge in said part adapted to be ignited by said cap, said projectile having a loading chamber, an expelling charge therein, a delay fuse for said expelling charge, and a passage to carry the flame from said percussion cap directly to the said fuse and propelling charge.

6. A cartridge for lire-arms comprising in combination, a cartridge case having a cylindrical bore for its full length, `a percussion cap in the base of saidA case, a projectile having a part closely and completely lling the Whole bore of said case, a recess in and opening to the rear of said part, a propelling charge in said recess, a loading chamber in said projectile, a signal pyrotechnic in said chamber, an expelling charge in the bottom of said chamber, a longitudinal tube entirely through said projectile part and recess leading from the percussion cap to said expelling charge, and a delay fuse in said tube.

'7. A cartridge for nre-arms comprising in combination, a cartridge case having a cylindrical bore for its full length, a percussion cap in the base of said case, a projectile having a part closely and completely lling the whole bore of said case, a recess in and opening to the rear of said part, a propelling charge in said recess, a loading chamber in said projectile, a signal pyrotechnic in said chamber, an expelling charge in the bottom of said chamber, a longitudinal tube entirely through said projectile part and recess from the percussion cap to said expelling charge, a lateral passage through the tube Wall to con-

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