FR2614096A1 - COMBUSTIBLE OBJECTS IN THE FORM OF ETUI BORGNE - Google Patents

Abstract

THE PRESENT INVENTION CONCERNS COMBUSTIBLE OBJECTS IN THE FORM OF A BORDER CASE FOR ARTILLERY AMMUNITION. THE OBJECTS ACCORDING TO THE INVENTION ARE OBTAINED BY SHAPING SHEETS OF FUEL PAPER CONTAINING NITROCELLULOSE AND ARE CONSISTED BY AT LEAST ONE CYLINDRICAL TUBULAR ELEMENT 5 AND BY A CLOSING ELEMENT 6, THE INSERTED ELEMENT RELATING TO THE EXTERIOR SURFACE ITS RECESSED PART OF GROOVES OR RIBS. WHEN THE RECESSED ELEMENT IS THE TUBULAR ELEMENT 5, THE LATTER CARRIES ADVANTAGEALLY ON ITS RECESSED PART WITH GROOVES 8 INCLINED WITH THE AXIS OF THE TUBULAR ELEMENT.

Description

Fuel objects in the form of a blind case

  The present invention relates to the field of combustible objects

  containing nitrocellulose for use in munitions, including artillery ammunition. More specifically, the invention relates to combustible objects in the form of a blind case

  such as in particular fuel sockets.

  Traditionally, a shell for ammunition is constituted by a body which is in the form of a cylindrical or conical tube, and by a bottom or base, carrying a priming system that comes

  close one of the ends of said body. The sleeve thus constitutes

  killed is filled with a charge of powder and is most often crimped to a shell to form the ammunition. There is also

  weapon systems, including artillery cannons, for

  the ammunition consists of a shell and an inde-

  hanging not set with the shell. The shell and the socket are set

  post in the weapon independently of one another. This type of muni-

  The advantage of allowing the sleeve to be independent of the shell is that it allows an adjustment of the amount of powder to be used in the socket, just before firing, in the field, as needed. Such bushings are constituted by a closed body at one of its ends by a bottom, by a powder charge placed inside said body and by a cover that closes the other end of said body. In most cases, there is also a setting disk placed inside the body so as to block the powder load and to prevent any

  displacement of the latter inside said body.

  In conventional ammunition the socket, whether it is a

  socket set to the shell or a socket independent of this

  deny, consists of a non-combustible metal material, usually brass. Such a socket has two disadvantages

  major because of the fact that its cost price is high,

  in the case of medium and large weapons ammunition

  free, and on the other hand that it requires, since it is incompa-

  bible, to be extracted completely from the breech of the weapon after firing, which is not without posing a number of difficulties, particularly in the case of weapons with a high rate of

  shot or in the case of weapons firing at high pressure.

  The person skilled in the art was therefore led to search for ammunition

  bearing a fully combustible socket which do not have the above-mentioned drawbacks and which in addition provide a

  supplement of energy by their combustion.

  Various attempts at solutions have been proposed in this

  Maine. It has thus been proposed fuel bushings constituting

  killed by explosive laden foam. Such a solution is for example described in French Patent 2,294,421.

  this type of solution is of a delicate and dangerous implementation.

  because it uses explosive and

  thinks it is bad for large ammunition.

  The skilled person has therefore turned to solutions using consumable fibrous materials such as cellulose which

  are, a priori, easier to implement.

  Generally speaking, a sleeve made of

  it is not sufficient that it contains organic hydrocarbon fibers such as

  cellulose, but it has been found that at least one

  of these fibers are nitrated to ensure combustion

  made and sufficiently fast which leaves no traces of

  dukes imbr les in the weapon. Various solutions have already been proposed for the realization

  of fuel sockets. Thus it has been proposed that

  to make combustible cases from textile fibers by continuously nitrating textile fibers, by assembling the nitrated fibers into ribbons which by winding around a mandrel

  give nitrated fiber holsters. This technique is for example

  ple described in French Patent 2,074,832 but is of a complex and delicate implementation, which greatly limits its interest in the mass production of fuel holsters to

cheap.

  It has also been proposed to impregnate sheets of paper with latexes containing nitrocellulose and to make combustible cases from paper sheets thus impregnated, but such a technique, for example described in the French patent.

  1,552,875, does not allow to obtain perfectly homogeneous cases.

  because the impregnation of the paper is not done perfectly

  homogeneous and moreover the combustion of such cases leaves ashes residues as it is said in the examples of this

  patent, residues that very quickly foul a weapon.

  It has also been proposed to manufacture fuel sockets

  by molding energetic compositions containing nitrocellulose. This technique, described for example in the French patents 2,240,258 and 2,278,660 in the name of the applicant, if it gives satisfaction as to the technical quality of the fuel sleeves obtained, is poorly suited to the manufacture of

  large series because of the inherent limitations of

  mold due to the immobilization of the molds themselves.

  the occasion of each molding operation.

  It has also been sought to manufacture fuel sleeves by felting an aqueous suspension containing nitrocellulose mixed with cellulose fibers. This technique is for example described in French Patent 2,234,113 in the name of the applicant. This technique gives excellent results for the manufacture of sockets for large arms and to be produced in relatively small quantities. But

  this technique, on the one hand by the very dimensions of the

  necessary for its implementation, and secondly

  production rate, is not suitable for the manufacture of

mass production.

  In order to make mass production possible

  bushings, attempts have been made to manufacture the various elements

  constituent elements of the socket from combustible paper

  containing nitrocellulose using the papermaking techniques

  ts. Thus, the French patents 2 485 182 and

  2,555,302 discloses the manufacture of fuel bushing bodies

  spiraling strips of fuel paper containing nitrocellulose and that the French patent applications 2,570,645

  and 86.04039 describe the manufacture of

  bursts and especially fuel pellets by stamping

  discs of combustible paper containing nitrocellulose.

  These techniques thus make it possible to manufacture in large

  the various fuel elements which, by assembly and, in general, bonding make it possible to constitute the fuel bushing or, more generally, the combustible object which is presented under the

shape of a blind case.

  The only problem that has not yet been solved so completely satisfactorily so far is that of the mechanical strength

  junctions between the different constituent elements of the ob-

  fuel jet. The combustible object taking into account its generic form

  Rale is formed on the one hand by a tubular element and on the other hand by a closure element having a substantially cylindrical wall whose outer diameter and inner diameter are such that one of said elements can be embedded in the au

  be. In order to strengthen the link between these elements

  In general, a glue is used but, at the time of introduction,

  duction of the different elements in each other this glue tends to be repressed and to ensure later

  that a line of gluing between the two elements and not one

  real bonding surface. Moreover, in the case where the closure element is embedded in the tubular element, this closure element tends to deform and to flow under

  the effect of a load and its cylindrical wall tends to become

  lidariser of the tubular element to which it is attached. This is particularly the case when the closure element is a fuel socket for a large caliber artillery ammunition involving the insertion into the socket of a charge.

important powder.

  The object of the present invention is precisely to remedy the

  disadvantages mentioned above by proposing

  paper-based techniques from paper

  containing nitrocellulose which, by way of

  to obtain combustible objects, and in particular fuel sockets, having a good mechanical strength of

  junctions between the tubular body and the closure elements.

  The present invention thus relates, as industrial products, to

  new types of fuel objects in the form of a blind case each consisting of at least one cylindrical tubular element and

  by at least one closure element having a sensing wall

  cylindrically, the outside diameter and the inte-

  of the said wall being such that one of the said elements

  can be embedded in the other at their cylindrical parts.

  characterized in that said embedded element is ob-

  held by shaping sheets of combustible paper containing

  nitrocellulose and in that it bears on the outer surface

  top of its embedded part a hooking relief.

  Preferably, said hooking relief is constituted by

grooves or ribs.

  The presence of a hooking relief on the outer surface of

  the embedded part of one of the elements allows both

  to ensure a good retention of the glue on the entire surface of

  and a good mechanical attachment of the contact surfaces of the two elements. In this way, shaped fuel objects are obtained

  blind cases and in particular fuel sockets whose

  closures do not tend to dissociate themselves from the

  tubular, even under the effect of important constraints.

  A detailed description of the invention is given below.

referring to Figures 1 to 6.

  FIG. 1 schematically represents a combustion object

  in which the flush element is the closing element

ture.

  FIG. 2 schematically represents a combustion object

  in which the insert element is the tubular element.

  FIG. 3 represents, in longitudinal section, a bushing

  bustible according to the embodiment shown in Figure 2.

  FIG. 4 represents, in external view, the body of the socket

  fuel shown in Figure 3.

  FIG. 5 represents, in longitudinal section, a bushing

  bustible according to the embodiment shown in Figure 1.

  FIG. 6 represents, in external view and on an enlarged scale, the

  base of the fuel bush shown in Figure 5.

  The invention therefore relates to combustible objects, such as, for example,

  full of fuel sockets in the shape of a blind case. Objects

  fuels 1 according to the invention are shown diagrammatically

  1 and 2. A combustible object according to the invention is constituted by at least one cylindrical tubular element 2 and

  by at least one closure element 3 comprising a magnetic wall

  4. The outer diameter and the diameter of the

  The wall 4 of the closing element 3 is such that one of said elements can fit into the other at their cylindrical portions. In the embodiment shown in FIG. 1 it is the closure element 3 which can be embedded in

  in the tubular element 2, the insert part 3a of the element

  3 in this case coinciding with its cylindrical wall.

  the embodiment shown in FIG. 2 is the tubular element

  2 which can be embedded in the cylinder defined by the wall

  cylindrical 4 of the element 3, thus determining an encased part

trable 2a of element 2.

  The invention relates to combustible articles for use

  weapons, each component of the object must be

  to be combustible. But according to a first

  of the invention, for reasons of malleability and

  In practice, the insert element must be obtained by forming sheets of combustible paper containing nitrocellulose. If the insert element is the tubular element

  as shown in Figure 2, the shaping will be done by

  sealing of fuel paper strips containing nitrocellulose

  as described in French Pat. Nos. 2,485,182 and 2,555,302, if the insert element is the closure element as shown in FIG. 1, the shaping will be done by stamping discs cut from sheets of combustible paper. containing nitrocellulose as described in

  French patent applications 2,570,645 and 86,04039.

  The manufacture of sheets of combustible paper containing nitrocellulose is made from an aqueous suspension containing nitrocellulose, fibers of organic, synthetic, vegetable or mineral origin, a resin and optionally a stabilizer

  such as diphenylamine and fillers such as talc,

  tungstic hydride or titanium oxide. As nitrocellulose can be used any industrial nitrocellulose having a rate

  less than 13,8%, provided that the nitrogen content of the

  pier coming out of the paper machine does not exceed 12%. According to one

  preferred embodiment of the invention, a content of

  trocellulose such as the nitrogen content of the paper coming out of the

  China paper is close to 9%. As fibers of organic origin cellulose fibers such as kraft fibers will advantageously be used, but the other natural or regenerated cellulosic fibers may equally well be suitable, including the

  mechanical or semi-chemical pulp fibers or viscoses.

  Polyester fibers or acrylic fibers are advantageously used as fibers of synthetic origin. The fibers of plant origin will advantageously be

  sisal and as fibers of mineral origin, it will be advantageous to use

the glass fibers.

  The presence of a resin is essential to improve the coherence

  between the fibers and the stability of the paper sheet.

  pier. Any organic resin having the property of flocculating on nitrocellulose or cellulose fibers and supporting a passage may be used as the resin in the present invention.

  on paper machine. The preferred resins are acrylic resins

  vinyl resins, butadiene-based latices such as butadiene-styrene or butadiene-acrylonitrile latices. It has been observed that it is necessary that the amount by weight of resin represents at least 2% of the weight of dry nitrocellulose and cellulose used, preferably a quantity of about 5% will be used. The weight ratios of nitrocellulose to other fibers can range from 80:10 to 80 and preferably 70:20 to 20:70. The concentration of solids in the aqueous suspension is essentially dependent on used paper machine,

  standards of use recommended by its manufacturer and specifications

  the desired product. At the output of the paper machine, the sheet obtained can be calendered, hot or cold, or not

to be calendered.

  According to a preferred embodiment of the invention, not only

  the built-in elements but all the elements

  of the combustible object will be obtained by shaping the

  sheets of combustible paper containing nitrocellulose.

  But this is not a mandatory condition for the

  of the invention and the person skilled in the art may, in

  In some cases, it is preferable to use other production techniques for non-embeddable elements, such as, for example, the felting of an aqueous suspension of cellulose fibers, nitrocellulose and resin, the shaping of nitrated wires or the molding of composition. as discussed above in

the state of the art.

  According to a second characteristic of the invention, the element

  door on the outer surface of the encas-

  Trable 2a or 3a a hooking relief. The said hanging relief

  is preferably constituted by grooves or by

  mosina language. It will be advantageous to use grooves when the element

  insert is the tubular element and ribs when the

  insert is the closing element.

  FIGS. 3 and 4 show a fuel bushing in

  which the sleeve body 5 constitutes the tubular element

  castrated in a fuel base 6 constituting the element of firm-

  ture. The base 6 comprises a substantially cylindrical wall 7 receiving the socket body 5. The socket body 5 is a cylindrical body whose recessed portion 5a is terminated by a chamfer 9. Over the entire length of the cylindrical portion of the recessed portion 5a of the socket body 5 have been formed grooves which, advantageously, are inclined with respect to the axis of the socket body 5. A first interest presented by the use of the papermaking techniques lies in the fact that the material obtained by these techniques is malleable. It is thus possible to manufacture, in series, spiraling strips of combustible paper

  containing nitrocellulose, cylindrical bushing bodies

  mass forming and then die-stamping these bushing bodies so that they have a chamfer and grooves using a calibration tool having jaws shaped frustoconical sectors bearing punches for

shape the grooves 8.

  The said grooves 8 are thus obtained by stamping without removing

  matter. The grooves may be parallel to the axis of revolution of the socket body 5 or inclined with respect to this

  axis. In the latter case the grooves may have inclinations

  sounds and create a cross network of grooves.

  The sleeve body 5 is thus prepared, glue is coated either the cylindrical portion of the recessed portion 5a of the socket body is, according to a preferred embodiment of the invention, the inner surface of the wall 7 of the base 6. It introduces then in the base 6 the sleeve body 5. The grooves 8 operate at the time of introduction into the base as glue tanks and thus ensure effective bonding to the surface 5a by avoiding the backflow of the glue to the bottom. advantageously,

  for the purposes of the invention, the total area presented by the

  grooves 8 should represent between 20% and 25% of the

  facing the encastable portion 5a of the socket body 5.

  A second interest presented by the use of papal techniques

  The reason is that the material obtained is not only malleable but also slightly plastic. It is so

  possible, just before the introduction of the socket body 5, of

  primer to the recessed part 5a of the latter a slight necking facilitating introduction by avoiding the risk of tearing of the wall 7 of the base and ensuring after recovery of its initial shape by the recessed portion 5a a perfect adhesion of the surface

  exterior of the recessed portion 5a against the integral surface

top of the wall 7 of the base 6.

  FIGS. 5 and 6 show another type of embodiment of

  bushings according to the invention. In this type of

  it is the base 11 which constitutes the closing element which is insertable in the tubular element constituted by the socket body 10. The base 11 bears on the outer surface of its

  cylindrical wall 12 ribs 13. Advantageously these nerves

  13 are circumferential ribs arranged in

  perpendicular to the axis of the base 11. It is possible to

  hold such a pellet directly by stamping disk disks.

  fuel in a matrix of the form corresponding to

  Dante by means of a deformable flexible punch as described in the French patent application 86.04039. Here again the introduction of

  base 11 in the socket body 10 will be facilitated by the elasticity

  cited by the wall 12 of the base 11. The combined action of the initial recovery of the wall 12 after introduction and

  the anchoring effect provided by the ribs 13 will ensure adhesion

  the outer surface of the wall 12 of the base 11 against the inner surface of the socket body 10.

  anchoring effect will be particularly effective when the

  13, as shown in Figure 6, will present a

  triangular shape. This adhesion can still be

  improved by the presence of glue arranged between the nerves

  13. Moreover, even in the event of significant stress resulting from the presence of a large charge of powder, the creep and the stalling of the base will be rendered impossible by the

2 6 1 4 0 9 6

by the presence of the ribs 13.

Example

  A fuel bushing for caliber ammunition was manufactured

  mm according to the embodiment shown in Figures 3 and 4.

  The sleeve body 5 was obtained by spiraling strips of combustible paper containing nitrocellulose, the base 6 being felted with an aqueous suspension of cellulose fibers,

nitrocellulose and resin.

  The insert part 5a constituted the lateral surface of a

  cylinder with outside diameter 163.8 mm and height 15 mm.

  After swabbing this part Sa had the following characteristics: a) a chamfer 9 from 2.8 to 1.6 mm

  b) 40 grooves 8 distributed over the cylindrical portion of the

  tie 5a. These grooves are arranged helically and inclined

  30 'from the axis of the socket body 5. These reasons

  are an available internal volume of about

  35 mm3 each and a total bonding area of 18cm2.

  For the introduction of the socket body 5 in the base 6 was caused a temporary shrinkage of the insert part 5a by compression so as to ensure a clearance of 0.3 mm at the time of

assembly.

  The assembly thus formed has a high mechanical strength since during uncoupling tests there is rupture of the bottom of the base 6 but not the tear of the junction

casing socket body.

Claims (8)

claims   1. A combustible object (1) in the form of a blind case constituted by   least one cylindrical tubular element <2) and at least one element   closure member (3) having a substantially cylindrical wall (4), the outer diameter and the inner diameter of the   said wall being such that one of the said elemen-   in the other at the level of their cylindrical parts,   in that the said insert element is obtained by setting   form of sheets of combustible paper containing nitrocell-   lulose and in that it bears on the outer surface of the part   recessed (2a, 3a) a hooking relief.   2. Combustible object according to claim 1 characterized in that said attachment relief consists of grooves or ribs. 3. Combustible object according to claim 2, characterized in that   that the insert element is said tubular element (5).   4. Combustible object according to claim 3 characterized in that said hooking relief is constituted by grooves (8).   inclined relative to the axis of said tubular element (5).   5. Combustible object according to claim 4 characterized in that   that the inclined grooves (8) constitute a crossed network.   The combustible article according to any one of claims 3 to   characterized in that the total area presented by all the grooves (8) is between 20% and 25% of the area of the   embedded part (Sa) of said tubular element (5).   Combustible object according to claim 2, characterized in that   that the insert element is said closure element (11).   8. Combustible article according to claim 5, characterized in that   that the said attachment relief is constituted by nerves   circumferential vests (13) in perpendicular planes.   to the axis of the cylindrical wall (12) of said closure member (11).