US3500715A

US3500715A - Firing equipment

Info

Publication number: US3500715A
Application number: US763838A
Authority: US
Inventors: Boris Batou
Original assignee: Mecar SA
Current assignee: Mecar SA
Priority date: 1967-10-03
Filing date: 1968-09-30
Publication date: 1970-03-17
Anticipated expiration: 1987-03-17
Also published as: GB1221553A; FR1594649A; IL30784A0; SE352946B; IL30784A; BE721431A; CH464736A; DE1801581A1

Description

March 17, BATQU FIRING EQUIPMENT Filed Sept. 30, 1968 1N VENTOR Boris BATOU ATTORNEY.

3,500,715 FIRING EQUIPMENT Boris Batou, Geneva, Switzerland, assignor to Mecar S.A., Brussels, Belgium, :1 firm of Belgium Filed Sept. 30, 1968, Ser. No. 763,838 Claims priority, application Switzerland, Oct. 3, 1967, 13,863/ 67 Int. Cl. F41f 1/06 US. Cl. S9-1 2 Claims ABSTRACT OF THE DISCLOSURE Noiseless, flameless and smokeless firing equipment comprises a meter having a breech at the rear of a barrel and a launching rod fixed in the breech. A projectile, which slides in and is guided by the barrel, has a front body and a tubular tail terminating in an annular restriction. Fins form a tail assembly of the calibre of the barrel. In the front of the tail, a piston is headed by a cap and an explosive charge. An annular flexible ring around the piston keeps the tail sealably spaced from the launching rod throughout its passage over the rod. By making the barrel twice the length of the rod, the projectile is kept guided even after propulsion ends. Defiections from correct trajectory of the projectile, due to misalignment of the launching rod, are thus obviated.

The present invention relates to firing equipment and more particularly to noiseless, flameless and smokeless firing equipment.

In previously known firing equipment, interfering effects occur during firing and arising from static (flaming) or dynamic (transverse vibration) effects.

It is an object of the present invention to provide firing equipment which overcomes these interfering effects.

According to the invention, there is provided noiseless, flameless and smokeless firing equipment, comprising on the one hand, a motar provided with a breech situated at the rear of a barrel and a launching rod arranged in the barrel in the neighborhood of the breech, and on the other hand, a projectile adapted to slide and to be guided in the barrel, said projectile comprising a front body fixed to a tubular tail terminated at its rear end by an annular restriction, and a tail assembly of the calibre of said barrel located at the read of said tail and a piston provided with a cap located in the front part of the said tail and behind a propulsive charge, said firing equipment being arranged in such a manner that, during the time in which the launching rod is inside the tail, the rod is without direct mechanical contact with the tail.

Conforming to the preceding structural arrangements, the projectile is only guided externally by the barrel of the motar, the launching rod having only the sole purpose of serving for the support of the piston on which the pressure of the propellent gases are exerted, but without providing any guiding action on the said projectile. In previously proposed equipment, the launching rod served not only to support of the projectile, but also guide the latter during the action of propulsion.

According to a specific embodiment of the invention, an annular space is maintained between the piston and the tail of the projectile, at the front and at the rear of an annular resilient joint.

Due to this fact, the displacement of the projectile along the axis of the barrel is ensured, even if the axis of the launching rod is slightly eccentric or oblique with respect to that of the said barrel, or again, even if the launching rod deflects slightly under the elfect of the load of the thrust and wherefore the piston might to be disaligned.

Due to the improvements according to the invention, it is now possible to launch a projectile of the type indicated in the manner of projectiles for classical mortars, that is to say, by effecting the automatic percussion of the projectile by guided fall into the gun barrel without the tail .of the projectile touching the launching rod at the time of its descent into the tube or at the time of the propulsion which follows percussion. The same improvements also find usefulness at the time of firing of a projectile of the aforesaid type in a mortar in which the start of the thrust is controlled by hand through a percussion mechanism.

In other words, the launching stern not being in direct mechanical contact with the tail of the projectile and the piston being able to be flexibly suspended in the cylinder which constitutes the tail, it follows that these two elements can only have a propulsive action without interferring radial effects, static (flaming) or dynamic (transverse vibrations).

In fact, experience has shown that, in the absence of the aforesaid arrangements, the effects of flaming and of transverse vibrations communicated to the piston during propulsion give rise to transverse stresses such that the wings of the tail assembly are deformed on contact with the surface of the bore of the barrel.

Other advantages and specific embodiments of the invention will emerge more explicitly from the description which follows:

In order that the invention may be more clearly understood, one embodiment of firing equipment according to the invention is described below purely by way of illustrative but non-limiting example, with reference to the accompanying drawing, in which:

FIGURE 1 shows schematically a partial axial section with tear-off of one embodiment of firing equipment according to the invention, immediately before percussion; and

FIGURE 2 shows schematically a similar section to that of FIGURE 1, immediately after percussion, at the beginning of propulsion.

In FIGURE 1, the reference 1 designates the barrel tube of a mortar terminated at its base by a breech 2 of which the ball-joint 3 is fixable on a base plate (not shown). A launching rod or propulsion rod 4, provided with a firing pin 5, is fixed by its rear end in the breech 2.

The projectile comprises a body 6, a tubular tail 7, screwed into the body 6, and a tail assembly 8 of which the ends of fins 9 are of the calibre of the bore of the barrel tube 1.

A cylindrical envelope 10, preferably of plastics material, includes at the front a flange 11 of larger diameter held by clamping between the front end of the tail 12 and the bottom 13 of the body 6. The rear part of the envelope 10 is fixed by gluing, crimping or any other way on the perimeter of a piston 14. Said piston comprises an axial channel in which is located a cap 15 held in place by a cylindrical bushing 16 being closed at its upper part by a pad 18 surrounded by a washer 19 in front of which is the propellent charge 20. An annular flexible joint 21 is housed in a corresponding groove of the piston 14.

An annular space 22 is arranged between the outer surface of the piston 14 and the inner surface of the tail 7. The piston 14, before percussion, is centered and held as much towards the front as towards the rear by the envelope of the plastics material 10.

Finally, an assembly of at least three ailerons 23, borne by a ring 24 itself fixed on the body 6, serves to guide the projectile in the barrel 1.

A second annular space 25 is arranged between the support rod 4 and a restriction 26 at the back of the stem 7, so that, according to the invention, the tail of the projectile is never in contact with the Propulsion rod 4.

FIGURE 2 shows the projectile described in FIGURE 1 at the beginning of propulsion, that is to say, immediately after percussion of the cap and the application of fire to the charge 20.

The piston 14, shown in FIGURE 2 separates from the envelope 10 under the effect of the deflagration of the charge which pushes the projectile upwards.

Under the effect of the strong initial thrust of propulsion, the rod may yield between certain elastic limits and be disaligned momentarily with respect to the barrel 1. There then follows transverse efiects of stresses and of vibrations of the rod and of the piston in the transverse direction, but without appreciable eifects on the tail of the projectile, these being entirely absorbed by the deformation of the flexible joint 21, considering that neither the piston 14 nor the rod 4 are in direct mechanical contact with the tail 7.

In other words, during the whole of the action of propulsion, the piston 14 and the rod 4 possess a degree of transverse freedom whilst the projectile, guided in the barrel 1 on the one hand by the tips of the fins 9, and on the other hand by the ailerons 22, follows its axial propulsion normally and without transverse effects resulting from yielding and vibrations of the rod 4.

At the end of the propulsion, the restriction 26, through a plastic ring 27, carries away the piston 14 which takes up the speed acquired by the projectile, whilst the gases expanded into the tail 7 remain imprisoned under the sealing effect which the joint 21 constantly produces. Whatever may then be the position of the rod 4, this has no transverse effects on the projectile, due to the annular space 25 maintained between the restriction 26 and the launching rod.

In a specific embodiment of the invention, the barrel of the mortar has a length greater than double that of the launching rod so that the projectile is still guided in the barrel after the end of the propulsion. It follows that, in all cases, at the moment when the projectile leaves the mortar, it cannot be subjected to any secondary stress whic can result from the propulsion. In a conventional mortar, on the contrary, the action of the gases exerts its effects up to the emergence of the projectile from the barrel and even when the projectile has already left the barrel of the mortar.

I claim:

1. Firing equipment comprising:

(A) a mortar including:

(1) a barrel (2) a breach at the inboard end of the barrel (3) a firing-pin-mounting launching rod of a length less than half the length of the barrel disposed in and centrally of the barrel and fixed at its inboard end to the breech (B) a projectile slidably disposed within and guided by the barrel and including:

(1) a body (2) a tubular tail having its outboard end fixed to the inboard end of the body and having an opening through its own inboard end for sleeved relationship to and spaced relationship from the launching rod (3) a finned tail assembly of the caliber of the barrel circumposed around the tail (4) an explosive charge disposed within the outboard end of the tail (5) a cap-mounting floating piston within the outboard end of the tail inboard of the explosive charge and supported by the launching rod during propulsion (6) an annular flexible ring circumposed about the piston for precluding direct mechanical contact between the piston and tail inboard and outboard of the flexible joint throughout the movement of the piston with respect to the launching rod.

2. In the firing equipment as set forth in claim 1 including: the explosive charge being located in a tube having a rear portion fixed on the front of the piston and having a flanged front portion clamped between the outboard edge of the tail and body.

References Cited UNITED STATES PATENTS 1,347,125 7/1920 Schneider 89l 3,134,330 5/1964 Batoll 89l 3,306,163 2/1967 Griessen 89-1 SAMUEL W. ENGLE, Primary Examiner US. Cl. X.R.