FR2665762A1 - PROJECTILES. - Google Patents

Abstract

A cannon-launched projectile shoe (56) (50) is configured to surround the projectile and has inwardly projecting flanges (60, 61) at its forward end which fit into grooves in the barrel. projectile so that at least part of the launching forces is transmitted to an anterior section of the projectile body by this means. Using the sabot reduces the thickness of the body wall behind the projectile, leaving more room for the sensors and associated electronic equipment.

Description

The present invention relates to sabots for projectiles and, more

  particularly but not exclusively, sabots for guided projectiles,

launched by cannon.

  Sabots are used to ensure the link between sub-calibrated projectiles and the barrel of a cannon These normally consist of two or more

  several parts separated so that they can separate

  rer of the projectile leaving the muzzle of the barrel It is usual to provide a securing ring at the front of the sabot and a shutter, which forms a joint

  gas between the shoe and the barrel tube at the rear.

  The shutter can also provide a means through-

  which the projectile is not subject to rotation conferred

caused by the scratch in the tube.

  In the production of guided projectiles, launched by cannon, it is desirable to provide an internal volume 2. as large as possible to contain

  detectors and associated electronic equipment.

  Thus, it is preferred that the wall of the projectile is also

  as fine as possible In addition, for aerodynamic stability

  that fin stabilized projectiles need

  a center of gravity located towards the front and this imposes

  the wall of the projectile is relatively thin

turn of its rear part.

  This condition may result in

  that the wall has a structural mechanical resistance

  inherent insufficient to support the forces

due to launch.

  According to one aspect of the present invention, a sabot means for a projectile is provided, this means

  being configured to surround the projectile and being

  determined to transmit at least part of the launching forces produced during the launching of the projectile

  from a launch medium, to an earlier section

  re of the projectile body, the hoof means being able to be

  separated from the projectile after its exit from the launcher means

  While transmitting part or all of the launching forces to the front part of the projectile,

  the shoe means also performs the important function

  aunt protecting the body of the projectile against

  very high gas pressures prevailing during the launcher

is lying.

  The use of the shoe means of this in-

  vention allows a significant reduction in the thickness of the rear wall of the projectile, for example from 5 mm in a conventional projectile to 1 mm in a projectile

  intended for use with the shoe of this in-

  vention. The shoe means comprises one or more formations intended to be placed in formations

  complementary to the body of the projectile.

  3. Preferably, the shoe means comprises one or more

  several ledges intended to engage in one or more

  several grooves in the body of the projectile.

  Preferably, the shoe means is intended

  born to separate into at least two parts at its exit from the launching means In another embodiment, the shoe means comprises a shoe part in several pieces; in another embodiment, the shoe means comprises an element having two or more grooves to facilitate breaking of the element into at least two parts after the projectile has left the launching means. Preferably, the shoe means comprises a

  posterior part which extends towards the rear of the projection

  tile and contains a plug means in charge transmission engagement with a portion of the rear of the projectile and which is intended to transmit at least one

  part of the launching forces at the launch of the pro-

jectile to this rear part.

  Preferably, the plug means and the rear part can each separate into at least two parts during or after the launching of the projectile by

the means of launching.

  In the case where the projectile is stabilized by fins, it is preferred that the support part of the

  fins be contained at least in part in the

posterior tie.

  Advantageously, the hoof means and the par-

  anterior tie can form the same whole.

  Preferably, sealing means are provided to prevent the penetration of propellant gases into the rear part during launching In a

  embodiment, the sealing means comprise

  a flexible element covering the rear end of the rear part In another mode of 4.

  embodiment, the sealing means comprise an element

  sealing associated with the rear part or by means of a plug, and in leaktight contact with the means of

  cap or with the back.

  Conveniently, the hoof means is used in

  the same time as a shutter means surrounding an ar-

  of the hoof means intended to provide a seal between the hoof means and the tube of the launching barrel In the case where the hoof element and the rear part

  are formed separately, it is preferred that the means of

  turator provides a seal between said part and the element

hoof ment.

  According to another aspect of the present invention,

  a sabot means is provided for a configured projectile

  re so as to surround the latter and transmit part of the launching forces to the projectile via a

  previous section, and send it another part

  tie launch forces via a rear section so as to distribute the load of the projectile during the

launch.

  Advantageously, the shoe means comprises

  a posterior part and a hoof element, the

  rear tie being configured to wrap the fins and extending forward to make the

  connection with the hoof element, and a piss element

  tone configured so as to enclose the fins and make the connection both with the rear of the projectile

than with the posterior part.

  The present invention will be well understood when

  of the following description made in conjunction with

  attached drawings in which: Figure 1 is a schematic side view, in section, of a guide projectile, launched by cannon; Figure 2 is a side view, partly in section, of a projectile equipped with a shoe means 5. according to the present invention; Figure 3 is a sectional view taken along line III-III of Figure 2; Figure 4 is a perspective view of a fin support ring;

  Figure 5 is a side elevation, in par-

  tie in section, of a projectile according to a second embodiment of the assembled shoe;

  Figure 6 is an exploded view of the shoe as-

  shown illustrated in Figure 5; Figures 7 a and 7 b are detailed views of the circle VII of Figure 5 illustrating construction variants; Figure 8 is a side elevation, partly in section, of a projectile according to a third embodiment of the assembled shoe; Figures 9 and 10 are cross-sectional views taken along lines IX IX and X X

  respectively of FIG. 8, parts being omitted

  its to make the figures clearer; and FIGS. 11 and 12 are partial views of variants of the piston for use in the mode

  for carrying out FIGS. 8 to 10.

  FIG. 1 represents a guided projectile, launched by cannon, represented broadly by the reference 10, which comprises a nose cone 12, a main body 14 and a rear body 16 The nose cone comprises a penetrator 18 and an element basic 20

  which forms a wall 22 separating the nose from the main body

  pal 14 A zone 24 of the main body 14 comprises a series of cavities for the fuel and each cavity

  has a thrust nozzle, one of which is shown

  tée en 26 The surface of the main body comprises two annular grooves 28 and 30 configured to receive the protrusions of a shoe A back plate 6. of closure 32 divides the main body 14 and the rear body 16 and carries a series of thin film igniters, one of which is indicated at 34 The rear body has a cavity 36 for housing a battery and electronic guiding components The wall 38 of the rear body is made of steel and is relatively thin so as to maximize the space available for electronic components The rear of the missile 10

  comprises deployable fins 40 and a lens.

  Figures 2 and 3 show part of the projectile, broadly represented by the

  reference 50, which includes several fins 52 to res-

  return spell, pivoting on its rear end The fins are kept folded in the direction of the interior, towards each other, by a retaining ring 53 comprising three fingers 54 extending forward, each finger having a turned end 55

  as can be seen in figure 4 The ring 53 can com-

  wear any number of fingers depending on the name-

  be projectile fins A sabot 56 in three parts

  ties is mounted around the body of the projectile 50 and main-

  held in place by two plastic rings 57

  and 58 which are each mounted in a circumferential recess

  ferential provided at the rear and at the front, respectively-

  another hoof circumference.

  giant in the shoe is located just in front of the ring

  rear 57 in order to support a shutter 59.

  Towards the anterior end of shoe 56, two

  annular flanges 60 and 61 project inwardly

  laughing from the inner surface of the shoe to enter respective complementary recesses

  formed in the body of the projectile The anterior end

  The bottom of each part of the shoe 56 has a part 62 chamfered directly inwards. Near its rear end, the shoe 56 has a groove 7.

  annular 63 directed inwards, -and three hollow-

  elements 64 a, b, c, which extend longitudinally between

  the groove 63 and the rear end of the shoe 56.

  When the shoe 56 is in place on the projectile 50, the retaining ring 53 can be mounted and the turned ends 55 of each of the fingers 54 can be inserted,

  holes in the groove 63 through the recesses

  ment 64 a, b, c We can then slightly turn the

  shoe 56 to block the ends 55 in the groove 63.

  Extensible cap 65 made of plastic material

  is mounted on the rear end of the shoe 56 The coif-

  fe 65 has a rear part of small diameter which is mounted by extension around the body of the projectile above the fingers 54 of the ring 53, and a part

  larger diameter front which is mounted by extension

  sion on the end of the shoe 56 The function of this

  cap 65 is to prevent gases under pressure, pro-

  fuel charge (not shown), does not penetrate below the shoe 56-at its end

posterior.

  Figure 3 illustrates the three parts of the

  shoe 56 in a sectional view and shows that each part

  tied to an edge 66 in abutment which is inclined relative to

  port in the radial direction This characteristic

  puts mount the shoe 56 in the shutter 59, that is

  that is to say that two parts of the shoe 56 can abut one

  against each other in the shutter, then that we can extend

  obliquely the third part to bring it in

  in shutter 59, then turn it and slide it

  ser to put it in its correct position compared to

  port to the other two parts In addition, with the rear fixing ring 57 in place, but not the front ring 58, one can open the front of the shoe 56 and make

  slide the shoe on the body of the projectile 50 from

  shot from the nose We can then close the front of the shoe 56 8. in the direction of the body of the projectile so that the flanges 60 and 61 enter their respective recesses

  coupling of the projectile, and we can position ltan-

  neau 58, while it is extended, in its recess.

  Alternatively, if the shutter is extendable so as to be able to slide on the shoe 56 in position on the projectile, the shoe can be made up of three

  parts which are abutting along faces extend

radially.

  In the projectile described above, if the launching pressure is applied directly to the rear part of the projectile 10, that is to say in the form of compression, the relatively thin wall 38 can

deform.

  In the embodiment described above,

  at least part of the acceleration force of the lan-

  cement is transmitted by shoe 56 to the relative walls

  thickly, which are therefore robust, to an anterior part of the projectile via the flanges 60 and 61 Not only, the flanges 60 and 61 are at a relatively great distance forward where it can be convenient that the wall of the projectile either relatively

  solid, but still, they have the effect of exerting a trac-

  tion instead of a push, on the projectile 50 coming out

  barrel tube, thus relieving compression at the-

  which the rear part of the projectile 50 is subjected during launching The shoe serves to protect the rear part of the projectile against the high gas pressure due to launching This pressure can be of the order of 350 M Pa and cause the curling of a wall in

thin steel.

  As will be noted, as soon as the projectile has left the barrel, the centrifugal force and the pressurized air entrain the parts of the shoe 56 outwards, breaking the rings 57 and 58 and 9. the shutter 59 La chamfered part 62 constitutes a

  sort of suction fan which helps with the fragmenta-

  hoof after launch The force of the breath

  of the launch acting on the rear also helps to separate

  rer the shoe 56 and the shutter 59 of the projectile 50 The

  chamfered parts can also be provided for ex-

  rear end of the hoof, if applicable As soon as the

  bot 56 is separated, the ring 53 also separates.

  Firstly in connection with FIGS. 5 and 6, a variant of a shoe means 70 comprises a

  cylindrical element 72 which consists of three parts

  ties 73, 74, 75 These parts are held on the projectile 76 at their anterior ends by a

  securing strip 77 which is mounted in a rai-

  nure 78 formed in the outer wall of each part

  tie, and at their posterior ends by a obturating

  assembled tor 79 mounting in another groove 80.

  The anterior end of the shoe element 72 presents

  two annular ribs 81, 82 projecting inwardly

  térieur, which engage in two annular grooves 83, 84 formed in the wall of the projectile 76 The assembled obturator 79 comprises two ring elements 85 and 86,

  which are mounted between the flanges 87, 88 of another element

  ring 89 made of a support material

  suitable such as polytetrafluoroethylene (PTFE).

  (We describe the shutter in more detail in our de-

  patent application 8602099) Its function is to ensure the seal between the shoe means 70 and the tube of the

  cannon with which projectile 76 is launched

  rear half 90 of the projectile 76 is covered with a cylindrical envelope 91 which constitutes part of the shoe means 70 and which encloses the fins 92 of the

  projectile, these being deployable outwards

  laughing and subjected to a return spring The casing 91 provides the connection with the shoe 72 with multiple pieces 10. at its anterior end 93 and is blocked therewith by a seal 94 In connection with FIGS. 7 a and 7 b,

  the seal 94 is an extension of the ring element 89.

  In FIG. 7 a, the extension part extends towards the rear.

  main ring and seal 94, and may have

  an inwardly directed lip which mounts on ex-

  hoppers of parts 73, 74 and 75 In FIG. 7 b, the flange 88, directed towards the rear, of the ring 89 is omitted and the

  extension of the ring ends with the gasket 94.

  A piston 95 is slidably received in the open end 96 of the casing 91 and has a shape allowing it to enclose the fins 92 and to be in contact with the rear end 90 of the projectile, the fins 92 being mounted in slots 97 formed in the piston 95 A sealing ring 98 is mounted in a groove made in the piston 95 and provides a

  gas seal between the wall

  100 of the casing 91 and the piston 95.

  During the launching of the projectile, the forces

  these launchers are transmitted to the front end of the projectile 76 by the engagement of the shoe means 70 in the grooves 83, 84 and to the rear of the projectile 76 by

  the pressure exerted on the piston 95 which transmits the

  this at the rear end 90 of the projectile This agency-

  allows to distribute the load to which the projection

  tile is subject because of launching Appropriately designed the shoe means can be brought to provide an optimal distribution of the forces of compression,

  so as to minimize the overall constraints to which

  the body wall of the projectile is subjected.

  After launching of the projectile by the barrel, the centrifugal force and the air pressure drive the parts 73, 74, 75 of the shoe 72 outwards

  breaking the securing strip 77 and sealing it

  assembled air 79 The air then enters the envelope there. cylindrical 91, causing the sliding towards

  the rear to get it out of the projectile.

  Now in connection with the mode of realization

  sation of the assembled shoe which is illustrated in FIGS. 8 to 12, this is similar in general to that just described, except however that the shoe 100 and the cylindrical part 106 form a "one-piece" construction and the shape and tightness

of the piston are different.

  The shoe 100 has a generally cy-

  lindrique comprising, near its anterior side, a

  pair of annular ribs 101 directed inwards

  laughing, which engage in a pair of grooves 102

  practiced in the body of the projectile in order to

  be forward thrust force transmission

  between shoe 100 and the projectile Three long slots

  tudinal 103 spaced the same distance extend

  between the front edge of the shoe 100 and an immediate position

  tally at the front of a groove 104 in which is

  killed a shutter 105 At the back of this position,

  in the cylindrical part 106 of the assembly, there has been

  ge three elongated interior grooves 107 for rup-

  ture, which have the same axis as the slots 103.

  At the rear end of the cylindrical part

  that 106 is a thick collar 108, the surface of which

  this interior receives in sliding a piston 109 having

  slots 110 to allow its mounting on the fins

  your stowed 111 of the projectile The outer surface

  collar 108 seals the periphery

  flexible membrane 112 which prevents trans-

  mission of the propellants in the cylindrical part

  than. As described above, the shoe is fixed to the projectile by means of a securing ring 113 placed in a front groove of the shoe.

  In connection with Figures 11 and 12, the pis-

  your 109 is designed to fragment during detachment

  hoof ching This can be obtained either in reali-

  the piston with a number of separate segments, two of which are indicated at 115 and 116, each being shaped so as to be mounted between adjacent fins (Figure 11), either by providing grooves

  the same axis as the slots 110 (Figure 12).

  In operation, when launched by the

  barrel tube, the assembled shoe is projected by a

  combination of centrifugal force and dynamic pressure

  air mique at the anterior edge of the hoof and breaks into three pieces Almost at the same instant, the piston 109 separates into six parts, also under the effect of centrifugal force and, thus, the size of the debris is

  which reduces the risk of damage

  management of the next projectile by this debris.

  As a variant of the embodiments

  described above, an assembled shoe could extend

  backwards and inwards so as to

  completely close the posterior part of the projectile.

  Thus, all of the launch pressure would be transmitted via the shoe assembled to the front part

* of the projectile.

  It is planned to manufacture the assembled shoe

  with a number of identical petals, for example-

  ple with three petals which, in use, would abut

  normally against each other.

  As another modification, the post-

  projectile could be covered with a

  flexible cup-shaped membrane with a

  thicker angular turn at its mouth, which abuts

  against the assembled shutter so as to make

  waterproof all the interstices at the back -

13. the shutter.

  This memo describes cylindrical projectiles

  bricks and hooves assembled in cylindrical form cor-

  However, it is envisaged that the shoe means of the present invention can be configured so as to mount a projectile having the general shape

  of a truncated cone or comprising a frustoconical pair.

  While the embodiments described

  surround projectiles launched by cannon, it will be understood that the shoe means of the present invention can also find applications in projectiles

  intended for launching: rockets from a smooth tube

  se. The present invention is not limited to the embodiments which have just been described, it is on the contrary subject to modifications and

  variants which will appear to those skilled in the art.

14.

Claims (13)

  1 Hoof block for projectile, charac-   terized in that it is configured to surround the projectile (10) and is intended to transmit at least part of the launching forces during the launching of the projectile by a launching means to an anterior section of the body (14 ) of the projectile, the shoe means (56) being able to separate from the projectile after   that the projectile has left the launching medium.   2 shoe means according to claim 1,   characterized in that it comprises one or more forma-   tions intended to be placed in com-   of the projectile body.   3 shoe means according to claim 2,   characterized in that it comprises one or more re-   edges (60, 61) intended to engage in one or more   several grooves in the body of the projectile.   4 Shoe means according to any one   of the preceding claims, characterized in that it   is intended to separate into at least two parts   after the projectile has left the launcher   is lying. Hoof means according to any one of   previous claims, characterized in that it comprises   takes a multi-piece element, the parts being intended to separate when the projectile has left the means launch.   6 shoe means according to claim 4 or claim 5, characterized in that it comprises an element having two or more breaking grooves so as to facilitate the breaking of the element in at least two parts after the projectile is released of the launching medium.   7 Shoe means according to any one   of the preceding claims, characterized in that it   15. comprises a rear part which extends towards the rear of the projectile and which contains a plug means (109) in charge transmission engagement with a portion   of the projectile directed outwards and which is   determined to transmit at least part of the forces   cement towards this portion during the launch of the missi-   the. 8 shoe means according to claim 7, characterized in that the plug means and the rear part can be separated, each into at least two parts, after the projectile has left the means of launching.   9 shoe means according to claim 7 or claim 8, wherein the rear part   is configured to wrap at least partially-   part of the projectile supporting fins your (111).   Hoof block according to one of the claims   cations 7 to 9, characterized in that the post-   is in one piece with the hoof element.   11 Shoe means according to any one   claims 7 to 9, characterized in that the element   hoof ment and the hind part are formed se-   facing and / o a shutter means (59) is used to form a seal between the rear part and the hoof element.   12 Shoe means according to any one   of claims 7 to 11, characterized in that it   includes sealing means to prevent   penetration of propulsion gases from the posterior part laugh during launch.   13 Hoof block as claimed   tion 12, characterized in that the sealing means   comprises a sealing element (94) associated with the part   tie back or by means of plug, and being in contact 16.   watertight with the plug means or with the rear part   laugh. 14 Projectile shoe means configured to surround the projectile and transmit part of the launching forces to the projectile via an anterior section and transmit another part of the launching forces to the projectile via a section   posterior so as to distribute the load of the projection tile during launch.   A hoof means according to claim 14, which is intended for use with a projectile comprising deployable fins (111) placed towards the rear and which comprises a rear part and a hoof element   (100) the rear part being configured so as to   expand the fins and extend forward to bond with the shoe member, and a piston member (95) is configured to enclose the fins and bond both with the rear   of the projectile only with the posterior part.   16 Hoof block according to any one of   previous claims, characterized in that the form me is generally cylindrical.   17 Shoe means according to any one of   Claims 1 to 15, characterized in that the shape is generally tapered.