US3888180A

US3888180A - Rod warhead

Info

Publication number: US3888180A
Application number: US774228A
Authority: US
Inventors: Eugene L Nooker
Original assignee: US Department of Navy
Current assignee: US Department of Navy
Priority date: 1968-11-06
Filing date: 1968-11-06
Publication date: 1975-06-10
Anticipated expiration: 1992-06-10

Abstract

The present invention is an improved booster for continuous rod warheads. Boosters in use up to the time of development of the present invention were so designed that the detonation wave produced thereby progressed radially at the detonator end of the warhead and then had to turn and move longitudinally thereof. This resulted in a non-uniform application of the detonation wave to the confronting rod elements and consequent uneven expansion and subsequent break-up of the rod projectile. The booster of the present invention, being of either hemispherical or conical shape (both embodiments being shown), ''''sees'''' the entire lengths of the rods and thus assures substantially uniform application of the forces of detonation thereto.

Description

United States Patent Nooker June 10, 1975 [54] ROD WARHEAD llirance 132/67 [,2 .i l 267 [75] Inventor: Eugene L. Nooker, San Luis Obispo, fame I Calif. [73] Assignee: The United States of America as j' i j rgf i J A Cooke represented by the Secretary of the gen 0 m Navy, Washington, DC.

[22] Filed: Nov. 6, 1968 ABSTRACT [21] Appl. No.: 774,228

The present invention is an improved booster for continuous rod warheads. Boosters in use up to the time [52] Cl 102/67 2 2 5,; of development of the present invention were so de- 51 Int. F42b 13/48; F42b 25/00 sgned "'9 dewnam wave Pmduced Field of Search 102/2 24 24 HC 67 70 progressed radially at the detonator end of the war- 5, head and then had to turn and move longitudinally thereof, This resulted in a non-uniform application of the detonation wave to the confronting rod elements [56] References Cited and consequent uneven expansion and subsequent UNITED STATES PATENTS break-up of the rod projectile. The booster of the 1,337,960 4/1920 Rid r H 02/2 present invention, being of either hemispherical or 2.698-575 V1955 Poulter 02/24 conical shape (both embodiments being shown), :Ookcr et alulm Sees" the entire lengths of the rods and thus assures empton Ell a 3249'050 5/1966 Cordlc at al A 4 v v [02/67 Isltgltaisgintttilzzilrlg3niform application of the forces of deto FOREIGN PATENTS OR APPLICATIONS 67,832 3/1958 France IO2/24 HC 11 Claims, 4 Drawing Figures 20 /4 l6 a; a la PATENTEDJUH I 0 I975 3 1 8 O SHEET 1 EUGENE L. NOOKER INVENTOR Tl Ow GM 00 PATENTEDJUH 10 ms SHEET INVENTOR ATTORNEY PATENTEDJUH I 0 ms :3 3 1 8 J SHEET 3 EUGENE L. NOOKER INVENTOR ATTORNEY PATENTED J5! 10 1975 I I v a f EUGENE L. NOOKER INVENTOR ATTORNEY ROD WARHEAD BACKGROUND OF THE INVENTION The booster comprising the subject matter of the present invention is an improvement over the one shown at 36 in FIG. 1 of US. patent application Ser. No. 666,543. filed Aug. 30, 1967. Eugene L. Nooker et al. inventors. Continuous rod warheads of the type with which the instant invention is adapted for use are shown typically in US. Pat. Nos. 3,224,371 and 3,223,036. The instant invention, however. is believed to be clearly patentable over the disclosures contained in the above mentioned patent application and patents, and over any other known prior art.

DESCRIPTION The present invention relates generally to continuous rod warheads. More particularly it pertains to an improved booster for warheads of this type.

In continuous rod warhead terminology the term "detonation geometry has been used to mean the aggregate of the detonation paths from the initiation point of the explosive charge to all points on the rods. The term also pertains to the related volumes of explosive and metal which serve to allow detonation wave thickness growth (total pressure-time) or rarefaction wave growth as well as those geometric factors which may affect. the complexity of the detonation wave structure.

In general, previous warheads have employed boosters that would produce the simplest practicable detonation wave paths. Similarly, the components were designed to include simple shapes free of odd corners, variable masses, etc.. so far as was possible. The study of detonation geometry has therefore been an active one and several experiments served to demonstrate its importance to continuous rod warhead behavior.

In earlier warheads it has been necessary to use a detonation system in which a single booster is placed with its axis coincident with the warhead axis. In such an arrangement the detonation wave progresses from the initiation point radially at the end of the warhead. It is then necessary for the detonation wave to turn-acorner" to progress to all points along the rods. Such an effect in the progress of the detonation wave may only affect the wave front and/or it may affect the wave structure. Thus. a hesitation" is produced in the wave that moves to the non-detonator end of the warhead as compared to the wave that moves to the detonator end thereof. A difference in timing of the wave components applied to spaced points along the rod lengths will therefore exist. leading to a more complex initial acceleration pattern for the rods, with consequent uneven projection and premature break-up thereof.

To provide a booster that will assure that the forces of the explosive charge will, upon initiation, be applied uniformly and simultaneously to the rods of the warhead throughout their lengths is the principal object of the present invention.

A more specific object of the invention is to provide a booster which, in all of its embodiments, will cause the detonation wave to travel evenly and without hesitation through the explosive charge from the detonator end of the warhead casing to the non-detonator end thereof.

As another object, the invention provides a booster that may be readily adapted for use with present continuous rod warhead casings with only minor modifications thereto.

Other objects, advantages and novel features of the invention will become apparent from the following description when considered in conjunction with the accompanying drawings, wherein:

FIG. I is a sectional view of a conventional warhead well known in the art.

FIG. 2 is an axial section ofa continuous rod warhead utilizing the booster of the present invention according to one embodiment thereof, the safety and arming unit of the warhead being shown in elevation.

FIG. 3 is an axial section of the warhead of FIG. I and showing a modified embodiment of the improved booster.

FIG. 4 is a view similar to FIG. 2 but showing a still further modification of the invention.

Referring to the drawings, and first to FIG. I, a warhead A according to the prior art is shown. In this view the booster, shown at B, is of cylindrical shape and is mounted within the casing on one end wall axially thereof and is embedded in a high explosive charge C of the warhead. A rod projectile is shown at D.

In the prior art warhead briefly described hereinabove, the booster B, when initiated by a suitable detonator E, produces a detonation wave which progresses from the initiation point in a radial direction at the end of the warhead, as shown by the broken lines F. As stated hereinabove, the detonation wave must turnthe-corner", as shown by the broken lines G. to cause the explosive charge to act on the rods of the projectile throughout their lengths. In other words, with the booster B, the detonation wave will move directly (radially) to impinge on one end of the projectile but must turn to engage the other end. Uneven acceleration of the rods thus results.

In FIG. 2, wherein one embodiment of the improved booster is shown, the warhead casing is shown generally at 10. The casing comprises a cylindrical side wall 12 about which is positioned a rod assembly 14. The rod assembly is of the double layer type, being similar to that shown in US. Pat. No. 3,223,036. The rod assembly is mounted between end rings 16 and I8 which also support the opposite ends of an outer buffer layer 20 and an outer skin 22. An inner buffer layer 24 is interposed between the innermost rod layer and the side wall 12. The forward and aft ends of the casing 10 are closed by

end walls

26 and 28, respectively.

Mounted in the casing I0 axially thereof and extending forwardly throughout the major portion of its length is a cylindrical housing 30 which is adapted to receive a safety and arming unit 32. As best seen in FIG. 2, the aft end of the housing includes a flange 33, which bears against the inner surface of the end wall 26, and an end portion which extends through an axial opening 34 in said wall. Suitable screws 35, which pass through a clamping plate 36, the end wall 26 adjacent the opening 34 and into the flange 33, secure the aft end of the safety and arming unit 32 in place on the end wall.

The safety and arming unit 32 at its forward end is provided with lead-in structure 37 including a lead sleeve which carries a detonator 38, that is embedded in the booster, to be described hereinafter.

Near its forward end the housing 30 is tapered in diameter, as shown at 39, to surround the lead-in structure, and is then flared outwardly to define a receptacle 40, the rim of which is secured to the rim of an opening 41 in the forward wall 28.

The improved booster is shown generally at 42, is of hemispherical shape, and is mounted in the receptacle 40. The booster includes a shell 43 which has an axial, inwardly directed sleeve 44 to receive the detonator 38 of the safety and arming unit 32. A bushing 45 surrounds the sleeve 44 within the tapered portion 39 at the forward end thereof. A backing plate 46 closes the shell 43 at its forward end, the plate being held in posi tion by an inturned flange 47 formed on the rim of the shell. Surrounding the housing 30 and extending throughout its length is an inner liner 48 which is formed of sponge rubber. An inner liner 49, also of sponge rubber, fits about the receptacle 40 and thus about the booster 42 within the casing 10. Entirely filling the interior of the casing and surrounding the housing 30 and booster 42 and their

respective liners

48 and 49 is a high explosive charge 50.

Reference is now made to FIGS. 3 and 4 of the drawings. wherein modified embodiments of the invention are illustrated. These views, though broken away, are similar in all respects to FIG. 2, except as to the booster modification per se. Accordingly, the reference numerals used in FIG. 2 will also be used in FIGS. 3 and 4 to identify corresponding parts, except for the booster.

In FIG. 3 the forward end wall 28 of the warhead cas ing 10 is imperforate and has mounted axially thereon, within said casing, a modified booster 52. The booster 52 is of generally frustoconical shape, having a flat forward wall which engages the inner surface of the wall 28, a flat aft wall, and a conical side wall which, in the example shown, is at an angle of 5 l /2 to the aft wall, for a reason to be stated hereinafter, said side wall hav ing a cylindrical base portion. The booster 52 is mounted in a receptacle 53 which has an opening 54 in its aft wall to receive the forward end portion of the leadsleeve 38 of the safety and arming unit 32, said forward end portion of said lead sleeve being embed ded in the booster 52. A liner 55 of soft rubber fits about the receptacle S3 and engages the forward end of the tapered portion 39 of the housing 30 and contacts the forward end of the liner 48.

In the embodiment of FIG. 4, the booster is shown at 56 and is similar to the booster 52, except that its side wall is disposed at an angle of 63 /2 to the aft wall and is devoid of a cylindrical portion at its base. The booster 56 is mounted in receptacle receptable 57 which is surrounded by a liner 58 that is similar to the liner 55. The receptacle is formed with an axial opening in its aft end wall to receive the forward end portion of the lead-in structure of the safety and arming unit 32, which structure carries the detonator 38 that is embed- (led in the booster 56.

The boosters described hereinabove each provide a direct path for the detonation wave from the initiation point thereof to the inner faces of the projectile rods throughout their lengths, so that there will be no turnthe-corner effect and there will be a more uniform application of explosive force to said rods. More specifically, with respect to the frusto-conical booster 52 of FIG. 3, the rod length seeing" an interface angle greater than about 80 is 2.4 nches, a considerable increase over the prior art booster of FIG. 1. The varia' tion in the angle to the rods is from 77 to 21 versus 64 in the prior art booster. The shape of the frusto' conical booster 56 of FIG. 4 is such that the interface angle region (of an angle greater than about 80) is centered on the rod length. The boosters of FIGS. 2 and 3 have the same angle range to the rods. It should also be noted that the taper of the forward end portion of the housing 30 and the liner 48 is such as to allow for an un-interrupted path from the booster initiation point to the rods.

The hemispherical booster 42 provides an even greater improvement, because the dimensions can be chosen so that the detonation path is always substantially to the interface. In other respects the wave approach to the rod is the same as for the frusto-conical boosters of FIGS. 3 and 4.

I claim:

1. In a rod warhead having a casing provided with a side wall, a projectile on the side wall and comprising a plurality of rods, and a high explosive charge in the casing and confronting the rods,

a booster in the casing and engaging the high explo sive charge, and a safety and arming unit in the casing and having a detonator engaging the booster,

the booster having wall means within the casing, said wall means having at least one point disposed in angular relationship other than zero degrees to that portion of the side wall which lies beneath the rods, whereby the detonation wave produced upon initiation of said booster will impinge on the rods substantially uniformly throughout their lengths.

2. The warhead as recited in claim 1,

wherein the portion ofthe booster which engages the high explosive charge is hemispherical.

3. The warhead as recited in claim 1,

wherein that portion of the booster which engages the high explosive charge is frusto-conicalv 4. In a warhead,

a casing having a side wall,

a projectile on the side wall and comprising a plurality of rods,

an explosive charge in the casing,

a booster in the casing and engaging the explosive charge,

and a safety and arming unit extending throughout the length of the casing and including a detonator extending axially into the booster,

the booster having wall means with at least one point disposed in angular relationship other than zero de grees to that portion of the side wall of the casing which lies beneath the rods, whereby the detonation wave produced upon initiation of said booster will clear the safety and arming unit and impinge on the rods substantially uniformly throughout their lengths.

5. The warhead as recited in claim 4, including addi' tionally a housing in the casing and surrounding the safety and arming unit,

an inner liner surrounding the housing in engagement therewith,

and an inner liner extending over the surface of the booster within the casing.

6. The warhead recited in claim 5,

wherein the housing and said first-mentioned inner liner are tapered at their corresponding forward ends to provide an unimpeded passage of the detonation wave from the booster to the rods.

7. The warhead as recited in claim 4,

wherein that portion of the booster which engages the high explosive charge is hemispherical.

8. The warhead as recited in claim 4,

wherein that portion of the booster which engages the high explosive charge is frusto-conical.

9. In a warhead having a casing. a projectile on the casing and a high explosive charge in the casing and confronting the projectile,

a housing mounted in the casing and having a tapered forward end portion,

a booster mounted in the casing and having a shell,

and

a safety and arming unit mounted in the housing and having a detonator extending into the shell.

inner liner is formed of sponge rubber.

Claims

1. In a rod warhead having a casing provided with a side wall, a projectile on the side wall and comprising a plurality of rods, and a high explosive charge in the casing and confronting the rods, a booster in the casing and engaging the high explosive charge, and a safety and arming unit in the casing and having a detonator engaging the booster, the booster having wall means within the casing, said wall means having at least one point disposed in angular relationship other than zero degrees to that portion of the side wall which lies beneath the rods, whereby the detonation wave produced upon initiation of said booster will impinge on the rods substantially uniformly throughout their lengths.

2. The warhead as recited in claim 1, wherein the portion of the booster which engages the high explosive charge is hemispherical.

3. The warhead as recited in claim 1, wherein that portion of the booster which engages the high explosive charge is frusto-conical.

4. In a warhead, a casing having a side wall, a projectile on the side wall and comprising a plurality of rods, an explosive charge in the casing, a booster in the casing and engaging the explosive charge, and a safety and arming unit extending throughout the length of the casing and including a detonator extending axially into the booster, the booster having wall means with at least one point disposed in angular relationship other than zero degrees to that portion of the side wall of the casing which lies beneath the rods, whereby the detonation wave produced upon initiation of said booster will clear the safety and arming unit and impinge on the rods substantially uniformly throughout their lengths.

5. The warhead as recited in claim 4, including additionally a housing in the casing and surrounding the safety and arming unit, an inner liner surrounding the housing in engagement therewith, and an inner liner extending over the surface of the booster within the casing.

6. The warhead recited in claim 5, wherein the housing and said first-mentioned inner liner are tapered at their corresponding forward ends to provide an unimpeded passage of the detonation wave from the booster to the rods.

7. The warhead as recited in claim 4, wherein that portion of the booster which engages the high explosive charge is hemispherical.

8. The warhead as recited in claim 4, wherein that portion of the booster which engages the high explosive charge is frusto-conical.

9. In a warhead having a casing, a projectile on the casing, and a high explosive charge in the casing and confronting the projectile, a housing mounted in the casing and having a tapered forward end portion, a booster mounted in the casing and having a shell, and a safety and arming unit mounted in the housing and having a detonator extending into the shell, said shell having a wall positioned to direct the detonation wave produced upon initiation of the booster by the detonator to clear the tapered forward end of the housing and impinge upon the projectile substantially uniformly throughout its length.

10. The invention as recited in claim 9, including additionally an inner liner of resilient material surrounding the housing in engagement therewith, the inner liner producing a time delay in the detonation of the charge.

11. The invention as recited in claim 10, wherein said inner liner is formed of sponge rubber.