Untitled record

PATENT

FRENCH REPUBLIC

MINISTRY

INDUSTRY AND TRADE

SERVICE Gr. H. _ Q. 4.

INDUSTRIAL PROPERTY

N ° 1.069.134

Αζ ^ 'UAcie ° .. t - 3 ^'

Priming systems for artillery shells.

Said company: SOFRANIC residing in France (Seine).

Requested on November 26, 1952, at 3 pm^h 45^m, in Paris.

Issued February 10, 1954. - Published July 5, 1954.

(Patent of invention whose delivery was deferred in execution of article 11, § 7, of the law of July 5, 1844 modified by the law of April 7, 1902.)

The present invention relates to priming systems for artillery casings.

It is known that the priming systems intended to ignite the propellant charge essentially comprise:

1 ° A device or device for igniting actuated for example by inertia or by any other means, this device having the role of igniting a first charge of small black powder (for example a few grams), it is generally contained in a tubular part called a primer holder tube;

2 ° A priming system ignited by the first charge of black powder; this ignition system is used to ignite the propellant charge proper contained in the socket, and therefore acts as a relay; it essentially comprises a greater charge of laying black than that contained in the ignition device, this charge possibly reaching a few tens of grams.

The present invention relates to the ignition system described above, with the exclusion of the firing device, the latter being of any type known or not.

The conventional primers currently produced generally consist of a metal tube of relatively small diameter and of relatively large length relative to the length of the socket; this tube extends the firing device and contains the charge of black powder, the cylindrical tubular wall of this priming system has vents serving for the passage of gases igniting the propellant charge, the basic idea of ​​this embodiment being that the charge of laying black burning pines quickly than the propellant charge, the adoption of the aforementioned form makes it possible to ignite the propellant charge in a very brief instant, over almost its entire height.

However, experience has shown that the initiating devices thus produced have several drawbacks, and in particular the following: 4 - 41088

During the ignition of both the priming system and the propellant charge, it sometimes happens that the tubular wall of the priming system cracks, and pieces remain after the start dn suddenly, inside dn cannon, which resulted in shooting incidents.

In addition, it seems that in some cases the speed of ignition of the black powder turns out to be lower than that of the propellant charge itself, so that the charge was actually ignited in these cases only through the first vents located near the firing device, the other vents then playing no useful role. This results in irregularities in the firing times.

Finally, the known priming systems are made in such a way that their installation inside the socket requires the prior installation of a primer holder tube, which makes the ammunition, despite all the safety measures taken, dangerous to transport and handle.

These drawbacks are avoided by the embodiments which are the subject of this patent.

According to the invention, the charge of black powder from the priming device, instead of being placed in a long and narrow tube, is collected in a compact cylindrical or annular shape of small height along the axis of the sleeve.

According to another characteristic of the invention, a cavity is provided between the primer holder tube and the charge of the priming system, and the shape of this cavity is studied so as to allow the ignition of this priming charge on a large area, from the flame created by the primer holder tube.

According to another characteristic of the invention, it provides in a variant a mechanical fixing independent of the priming device on the plate of the bushing, this making it possible to place the primer holder tube only after transport and handling, and practically just before

Booklet price: 100 francs.

The use of the ammunition, one at least after complete preparation of the ammunition.

Other characteristics of the invention will appear during the following description of two embodiments indicated by way of illustrative and nonlimiting example.

Figure 1 shows a first embodiment; it shows a meridian cut. We see in 1 the socket plate having in its center an orifice receiving the primer holder tube 2 which is fixed to it, for example by screwing or by forcing. The members of this primer-carrying tube of any known type are contained inside a cylindrical tube 20 fixed as indicated, on the plate 1. This tube has at its front end. an opening 3 closed for example by a tin disc.

The drawn primer holder tubes are of a conventional type. Note, moreover, that it is possible to use, instead of primer-carrying tubes, nipples.

In accordance with. the invention, the priming system is constituted by a charge of black powder produced in the form of a torus-shaped pancake and whose section is shown in 4 and 5.

This wafer is pressed between two metal plates 6 and 7, by means of a felt shim 8 and cardboard shims 9 and 10.

The black powder cake is protected towards the outside by an annular ribbon 11 which can advantageously be constituted by a tin-lead alloy playing the role of desencuivrant.

The plates 6 and 7 are clamped by the flanges 13 and 14 of a tube 12 surrounding the tube 20. This tube 12 is itself fixed on the outside of the tube 20 by forcing, screwing on any other lair, it comprises as illustrated, to the right of the load 4-5, nn a number of vents 15, for example four in number.

These vents, in connection with the opening 3, have the role of allowing the flames coming from the charge contained in the primer holder tube, to ignite the internal wall of the wafer 4-5.

In accordance with the invention and in order to allow this charge 4-5 to ignite simultaneously over its entire height, the internal diameter of the pancake is chosen as indicated, greater than the external diameter of tube 12, hence the existence of an annular vacuum allowing the flames passing through the side vents 15 to ignite the charge 4-5 over its entire height.

The annular vacuum can be replaced by longitudinal grooves made in the tube 12 in line with the vents 15.

The ignition of the propellant charge proper takes place through the ribbon 11 playing the role of desencuencrant.

Experience has shown that the flame thus obtained produces an energetic, rapid and regular ignition of the propellant charge proper, which results in good regularity of fire, absence of dispersion, and in the case of simultaneous firing of several guns ( for example guns under turret), no mowing harmful reaction from a eddy caused by a shell on the trajectory of a shell lair.

FIG. 2 shows an alternative embodiment making it possible in particular to directly attach the priming system to the plate of the socket without using the primer holder tube for this purpose. It also represents a meridian cut. We find in 1 the socket plate with in its center an annular orifice serving in particular for housing the primer holder tube 2.

The priming charge 21 is here produced in the form of a pellet contained inside a sort of cup 22 with an open bottom; this cup further comprises side vents 24; the cup is fixed directly to the plate of the socket by virtue of its tubular extension 25 through the bearing 26.

The bottom of the cup is closed by a disc 23, for example of tin-lead alloy.

The cup naturally includes a lower orifice 27 forming a borehole, inside which is placed the primer holder tube which is fixed to it by the bearing 28.

It can be seen that this arrangement does not require the prior fixing of the primer or choke tube to the bushing plate; on the contrary, the priming system serving to support the primer holder tube must be put in place before the latter which can be placed later at any convenient time.

The cake 21 rests on the bottom of the cup by means of an annular washer 30 advantageously made of felt. Here also, provision has been made between the black laying cake and the bottom of the cup, a free space 31 allowing simultaneous ignition on mowing its surface, in the bottom of the cake by the flame of the primer holder tube.

The operation of this variant is immediately understood from the foregoing explanations.

We see that in this case the manufacture of the ammunition includes the following operations:

1 ° Installation of the priming system inside the socket;

2 ° Installation of the propellant charge and possibly crimping of the shell;

3 ° Installation of a primer holder tube.

It is clear that many variants of the invention can be envisaged, without departing from the scope of this patent; in particular, in the embodiment of Figure 2, it can be arranged that the primer holder tube is fixed not by the bearing 28 but by a bearing 29 directly on the plate of the socket.

The systems described offer the great advantage of allowing their immediate application to existing sockets.