US 621085 A
Description (OCR text may contain errors)
No. 62I,085. Patented Mar. I4, |899.
(Application filed Jan. 7, 1899.) 6F40 Model.) l 2 Sheets-Sheet I.
A fro/,WE ys m. 621,085. Patented mar. I4, |899.
G. HuoKHAm. AUTOMATIC GUN. (Appliction filed Jan. 7, 1899.)
2 Sheeis-Sheei 2.`
frEs j GEORGE HooKHAM, E BIRIvnN'GHAM, ENGLAND.`
SPECIFICATION forming part of Letters Patent N o. 621,085, dated March 14, 1899.
Application flea January 7,1899.
.To a/ZZ whom, it may concern/:
Be it known that I, GEORGE HooKHAM, engineer, a subject of the Queen of Great Britain and Ireland, and a resident of New Bartholomew street, in the city of Birmingham, England, have invented certain new and useful Improvements in Automatic Guns, (for which I have made application for Letters Patent in Great Britain, No. 5,184, bearing date Marchy 2, 1898,) of which the following is a specification. This invention relates to automatic guns;- and its .object is to more effectively cool the barrel of such guns without the use of Water.
The invention consists generally in a combination of heat-radiating ribs or surfaces at-m tached to the barrel and a mechanical airdraft induced by each discharge of the gun and in any means employed to produce such mechanical air-draft where the impulse of the gases as they leave the muzzle at each discharge acts as a pump or ejector..
The accompanying sheets of drawings illustrate various methods of carrying the invention into eect. Y ,v
Figure l is a longitudinal section through the front end of an automatic or magazine gun, illustrating the mechanism employed to produce theA induced draft. Fig. 2 is a similar longitudinal section with certain variations in the position and shape of the coolingribs. Fig. 3 is also a longitudinal l section similar to Fig. 1 with a thirdvariation inthe shape of the cooling-ribs. Fig. 4 is a transverse section on the linea b, Fig. 3. Figs. 5 and 6 are part longitudinal sections through theimproveddevice,illustratingfurthermodiications in the arrangement of the coolingribs. Figs. 7, 8, 9, and 10 are longitudinal sections of alternative forms of ejector-nozzles which may be employed. Fig. 11 is a part side elevation of one arrangement of the cooling-ribs applied to a .303 automatic or Fig. 12 is a transverse section on the line c d, Fig. 1l.
In carrying the invention into eect, as illustrated in Fig. 1 of the drawings, the construction and operation are as follows: The barrelA of an automatic magazine-gun toward the rear end B is increased in diameter, as
Serial No.l,492. (No model.)
ber of radiating-ribs C are formed. These radiating ribs C are clearly shownv in the.'
v The eX- treme rear of the barrelD is-lnotl'iiuted,..but
transverse sections, Figs. 4 and 12.
passes or slides through a bush carriedwith the ordinarymechanism of the magazin gum so that upon discharge the travelofgthe barrel due to the recoil is allowed fory--`Attached to 4anysuitable portion of the ordinary g'unmechanisxn distinct from the barrel is a chambered piece, such as E, and this chambered piece has screwed, riveted, or. otherwise fixed toit a long sleeve or casing F, inclosing both the fluted land plain portions of the gun-barrel and terminating at the outer end in a removable nozzle, such as G. rlhe chamber E leads by suitable port or passages H to atmosphere.
When the machine-gun is in use, it is evidentl the containing-casing F an ejector-or pumping action will be set up b y thel sudden rush of the expanding gases into atmosphere, so that strong air-currents will be induced to lOW over the ribs of the barrel in the direction clearly shown by arrows. It is further evident that the velocity and volume of this aircurrent will depend upon 'the shape and size of the containing-nozzle within which the gun discharges and the shape and size of the passages and radiating ribs of-.t'he casing F and gun-barrel B, and it is always preferred to so arrange the conical nozzles or other terminations within which the gases produced by the explosion act to form an air-ejector of such an area that great volumes of air are dragged over'the cooling-surfaces.
Fig. 2 of the drawings illustrates a cooling arrangement of a somewhat similar nature to that shown in Fig. l, the parts which are not modified having like letters to that figure. The modification consists in providing the exterior containing-casing F with a series of transverse radiating rings I, preferably formed integral with the said casing and approaching to within a short distance of the fluted portion B of the gun-barrel A. By this arrangement the major portion of the inshown, and this rear end is spirally flutedror Vgrooved in such a manner that a large` num- IOO Figs. 3 and 4 of the drawings illustrate a cooling arrangement also ofV a somewhat similarv nature to that shown in Fig. l, the parts which are not modified having like letters to zthat figure. The modication illustrated in these figures consists in arranging the containing-casing F with a number of longitudinal radiating ribs both on the interior and exterior of the casing. The exterior ribs are lettered jK and the interior J, and their shape andarrangement'are clearly shown in both the figures in question. The operation of this modification is precisely similar to those hereinbefore described and therefore requires no further description. Arrows again indicate the ow of the induced air-current. o
Figs. 5 and 6 are partial views which illustrate further-modifications of the` radiating ribs. In Fig. 5 a spiral rib L is formed around the gun-barrely A, and the interior surface of the casing F almost touches ,the saidv spiral, so that the air-current induced by the nozzle would be forced to takea helical course around the barrel. Fig. 6, onv the other hand, shows rings M and 'N attached alternately to the barrelA and the cas'in g F, so that the induced air-current would take a tortuous path alternat'ely toward the casing and toward lthe barrel.
The different forms of nozzles illustrated in Figs. 7, 8, 9, and lO may be employed as substitutes for the ynozzle'Gr when required. Fig. 7 is a nozzle of ordinary construction, where 'the diameter is gradually decreased toward the exit.
of its length and then rapidly expandsagain, straight line surfaces being employed. In Fig, 9 the nozzle isat its smallest diameter about the center of its length; but the increases in size are less rapid, and the lines are curved. In Fig. lO the smallest diameter is nearly coincident with the mouth of the gun- In Fig. 8 the diameter of-the -nozzle quickly decreases to about the center barrel about a first third of the nozzles length,
and a gradual increase'toward the orifice then l takes place.
Figs. 11 and :12 show full-sized drawings of portion of the rear end B of a .303 magazinegun, illustrating the special form `of radiating rib and spiral grooves which it is preferred to employ in all the modifications. The grooves O practically amount to a great number of screw-threads or helices of very large pitch cut upon the increased diameter B of the gun-barrel A.
It is to be clearlyunderstood that any form of vejector-nozzle may be applied to the casing and also that anyform of radiating rib may be attached to either the casing or the gun= barrel.
Having now described my invention, what 4I claim'as new, and desire to secure by Letters Patent, isl l1. In combination in a gunwith the barrel, the casing inclosing the barrel open at the .rear to the atmosphere and terminating at its front end in a nozzle extending beyond the barrel, the space between the barrel and the casingbeiug partially filled or obstructed by projections, substantiallyas described.
2. In combination, the gun-barrel having a portion of increased diameter comprising spiral lutings on its exterior and acasing surrounding ,the barrel having a nozzle at its front end and air-inlet openings at its rear end, substantially as described.
' 3. 'In combination with the gun-barrel having the spiral iiutings on the outside thereof, the casing having the exterior and interior ribs and surrounding the barrel, said casing having a nozzle at its'front end and air-inlets at its rear end, substantially as described. y
I In witness whereof I have hereunto set my hand in presence of two Witnesses.
A. CHAMPENDAL, H. KARCHER.