US2757611A - Shaped charges - Google Patents

Description

g- 1956 JJH, CHURCH ETAL SHAPED CHARGES 2 Sheets-Sheet Filed April 11 1950 Joseph H. Church Gregory U. Kelslsenich Aug. 7, 1956 J. H. CHURCH ETAL SHAPED CHARGES 2 Sheets-Sheet Filed April 11 1950 v I l t I I SHAPED CHARGES Joseph H. Church, Austin, Minn, and Gregory J. Kessenich, Madison, Wis, assignors to the United States of America as represented by the Secretary of the Army Application April 11, 1950, Serial No. 155,313

2 Claims. (Cl. 102-24) Our invention relates to a new and novel form of shaped charge having a variety of useful applications.

It is a principal object of our invention to provide in one embodiment thereof a charge adapted to form and concentrate a jet for irnpiugement upon a target with a magnitude of force heretofore unobtainable with shaped charges provided with conventionally shaped cavities.

A further object of our invention is to provide in one embodiment thereof a form of lined shaped charge which will very substantially increase the density of the concentrated jet formed by detonation of the charge, whereby greater depth of target penetration may be obtained.

Another object of our invention is to provide one embodiment thereof which is especially useful in attacking a target located in a congested environment, to effect penetration upon a radius larger than the radius of the charge.

With these stated objects and many others which will be made apparent in the following description when considered with the drawings, in which;

Fig. 1 is a vertical sectional View through one embodiment of our invention disclosing the manner of shaping the cavity to obtain increased force effect and jet density;

Fig. 2 is a sectional view taken upon the line 2-2 of Fig. 1;

Fig. 3 is a vertical sectional view similar to Fig. 1 showing a slightly modified embodiment in that an additional axially disposed charge portion has been provided;

Fig. 4 is a sectional view taken upon the line 4-4 of Fig. 3;

Fig. 5 is a sectional view similar to Fig. 1 showing a modified form of charge which may be used as a unitary charge as shown or as two separate and distinct charges; the lower charge portion functioning as in Fig. l to concentrate the jet upon a comparatively small generally circular area, and the upper portion of the charge functioning to form an annular jet which at proper standoff use of the charge will impinge upon the target on a greater radius than the radius of the cavity;

Fig. 6 is a sectional view of a multiple shaped charge,

each element of which is similar to the charge shown in Fig. 1 and with each element arranged to axially concentrate the jet formed by the element at the same point;

Fig. 7 is a sectional view taken upon the line 7--7 of Fig. 6; and,

Fig. 8 is a diagrammatic illustration disclosing one method of detonating shaped charges of the type disclosed by our invention.

Referring now to the drawings there is shown in Fig. 1 one form of shaped charge constructed in accordance with our invention. We describe the charge 10 as being in the form of a solid which is defined or generated by revolving the plane area ABCD--E about a longitudinal axis of symmetry, or reference line RR which is contained in a plane containing the plane of the area ttes Patent A-BCD-E, or in short the plane of the area. The plane area ABCDE together with the reentering side or end AED thereof is generally symmetrical about a second axis or line of symmetry S-S and may be of any appropriate shape. Although the cavity is shown as being generated by the revolution about axis RR of two intersecting straight lines AE and DE, themselves symmetrical about axis SS, it will be understood that these lines may define any of the conic section forms appropriate for shaped charge use or portions or modifications of such conic section forms, or may be of helmet, bottle, ogee, gambrel roof, bell or any other suitable form so long as they are symmetrical about the axis or line of symmetry SS. Or, stated in another way, the lines A-E and D-E, forming the generatrix of the cavity, may be regular curves so long as they are generally symmetrical about axis SS and diverge from a common point B toward the adjacent end of the charge. In the generation of the chargeas a solid by revolving the area as above stated the cross-sectional shape of the cavity 11 will be dependent upon the shape of the reentering side or end A--ED and may be of a shape conforming to anyone of the above enumerated shapes of reentering side or ends AE-D that we contemplate being utilized. In all cases the cavity formed by generating the shape of the charge 10 as aforesaid will be toroidal.

In generating the shape of charge 10, we particularly desire to call attention to the fact that the area ABC-D-E is revolved with the line of symmetry SS thereof so that as prolonged outwardly of the reentering side or end A-ED it will converge with and intersect the reference line R-R at a preselected point P, in the same manner as the lines of symmetry intersect the reference line as shown at P in Fig. 6. The point P will vary with the parameters used in designing the charge, however, the arrangement will in all cases cause the jet formed by detonation of the charge, under use of the charge at the'designed standofli' parameter, to axially concentrate upon or focus upon or in close proximity to point P, which of course will be a point on the target. The total effective force applicable to point P by this arrangement isof a much larger magnitude than the force available from shaped charges now known in the art, as for example, if the explosives used in the conventional charge and the charge of our invention are considered to develop approximately the same unit pressures upon detonation, the form of our charge provides a considerably greater total area subject to unit pressure in formation of the jet and hence a greater total effective force.

The charge 10 is suitably encased in a container generally indicated at 12 and is provided with a liner 13 fitting the cavity 11 and formed of any metallic or nonmetallic material appropriate for such use.

The liner will be proportioned in thickness to the kind of liner material employed and in proper ratio to the other parameters used in the design of the charge, depending upon the size and character of the slug desired or whether it is desired that any slug survive the detonation process at all. Where angular shaped liners are used the apex angle can be varied to give optimum performance with the other parameters used as now well understood in the art.

Detonation of the charge 10 may be achieved by any satisfactory system for such purpose, as for example, the detonator system shown in Fig. 8 which is arranged to detonate the charge simultaneously in an annular zone 14 which may be located centrally of the charge as shown, or in an annular zone of greater or lesser radius than the radius of the zone 14 as indicated as desired. To accomplish the stated simultaneous annular detonation the charge 10 is shaped at the upper portion thereof as shown in Fig. 8 and a somewhat conically shaped detonator 15, as diagrammatically shown, is arranged for annular detonation communication with charge 10 at 14 as shown. The detonation of detonator 15 is initiated by the initiator 16 which may be of the electric type, or of any other suitable type which will initiate detonation centrally of the detonator 15, whereby the detonation wave will uniformly travel circumferentially to annular zone 14 to effect simultaneous detonation of charge 10 in this annular zone and thereby effect uniform collapse of liner 13 by uniform detonation of the explosive 17 of charge 10.

To prevent sympathetic detonation of charge 10 by virtue of detonation waves emanating from the adjacent portions of the inner wall 13 of charge It? the inverted conical space formed by the inner wall 13 may be filled with inert packing material 19 which will absorb the energy of these detonating waves to the extent of serving as a barrier to effective detonation transmission thereof.

It will be observed that the jet density will be increased when a liner of the form disclosed by our invention is used because of the greater volume of liner material injected into unit volume of the jet in unit time as compared to conventional liners. Although the density of the jet is increased there is less likelihood of spreading of the jet than in the case of a conical or similar liner since the liner collapsing forces are instantaneously acting in any particular transverse cross section so as to eliminate or mutually compensate for the effects of the factors that enter the spreading phenomenon, such as nonhomogeneity of liner material, etc.

We desire that it be understood that while we have shown the charge 10 as being of generally annular shape that we do not regard our invention as being limited to this shape since we may generate the charge by revolving area A-BC-DE only partially about reference line RR, thus forming the charge 10 in the form of a segmental annulus rather than an annulus proper.

The modification shown in Fig. 3 is quite similar to the form shown in Fig. l and to facilitate comparison like elements are indicated by the same reference characters. The principal difference between this form and the form shown in Fig. 1 lies in the distance of the adjacent or inner wall 18 of charge 10 from the reference line R-R when generating the charge form. In Fig. l the adjacent or inner wall 18 of charge It) as generated by line A--B in revolving area Al3--CD-E, is formed by arranging line AB substantially in contact with reference line R-R at point A so that the lower edge of wall 13 as viewed in Fig. 1 would theoretically terminate in a point. In the form shown in Fig. 3 the point A of line AB is spaced a distance K from reference line R-R so that in generating the charge form the inner wall 18 will terminate in an annulus 20 of predetermined diameter dependent upon the value of K as most clearly shown in Fig. 4. A shaped charge 21 conveniently illustrated as being of external cylindrical configuration and having the usual shaped cavity in any of the well known forms and provided if desired, with a complemental liner 22, is axially affixed at any desired location upon reference line R--R to act through annulus 21) along the reference line. The charge 21 and charge it) are organized as a unitary charge. The charge 10 in this composite charge may be detonated by the system shown in Fig. 8 as above explained and initiator 16 may be used to simultaneously initiate charge 21 through detonator 23. If preferred charge 21 may be detonated prior to or subsequent to detonation of charge 10 through the use of a timed delay control of detonator 23 from initiator 16, as well known in the art, or by independent initiation of ,detona-tor 23 so as to obtain conjoint action of the jets of both charges or the sequential action of the jets of the two charges in desired order.

In the modification illustrated in Fig. 5 there is shown a composite charge comprised of a lower charge 25 which is of a form that is generated in the same manner that the form of charge 10 was generated as above explained. This composite charge also includes an upper charge portion 26 which is symmetrical on the line of symmetry of the lower charge portion but having the reentering side or end Z--Y-X opening on the line of symmetry SS in a diverging direction of the line SS relative to the reference line R-R. The charges 25 and 26 may be simultaneously detonated by the dctonator assembly 27 which is similar to the detonator assembly shown in Fig. 8. The charge 25 will form a jet when detonated which will impinge upon the target in a small zone at or in the proximity of point P whereas the charge 26 will impinge upon an opposed portion of the target through an annular zone of radius L at standoff H which is larger than the radius I to the intersection of the cavity 28 shape and reference line R-R. The two charges 25 and 26 may he fired independently or in sequential order in any situation indicating such employment by the use of separate detonator systems for the two charges or the charge 26 may be utilized for its designed function entirely independently of charge 25. As in the case of charge 10 the inverted conical space 29 may be charged with inert material.

The modified form of charge disclosed in Fig. 6 illustrates a composite charge comprised of any desired number of concentrically arranged charge elements, which in the example here shown comprises two charge elements 3%) and 31, each of which is generated as to form in a manner similar to the manner in which the form of charge 10 is generated as above explained. Each out wardly succeeding charge element, such as the charge element 31, encompasses the next adjacent inwardly disposed charge element such as the charge element 30 and all charge elements, the elements 30 and 31 in the example shown, are in an axially vertical view as in Fig. 6, concentrically arranged about point P, the point of intersection of reference line R--R and the lines of symmetry S--S of the individual charge elements 30 and 31, so that the jets formed by detonation of the charge elements will all be focused to impinge upon the target in a small zone at or in close proximity to point P. The charge elements 30 and 31 may be detonated by a detonator system such as that shown in Fig. 8 and may be detonated simultaneously or in preselected relative sequential order.

Where charges 10, 25, 3G or 31 or charges of this type are used in warheads a suitable point initiating system for detonation of the charges from the bases thereof may be used and when located along reference line R-R may be so disposed as to not interfere with jet formation.

It is thus apparent that our invention consists basically in a shaped charged cavity generated by the rotation about a central longitudinal axis of symmetry, of a pair of intersecting lines, whose hisector is related at an acute angle to the aforesaid axis and intersects the same at a point forwardly of the charge and which lines diverge forwardly. The species of Fig. 6 is basically the same in function except only that the cavity is generated by two pairs of lines Whose bisectors are angularly related and intersect the axis of generation substantially at the same point forwardly of the cavity. In both cases the axis of generation and all lines are coplanar.

We claim: i

1. A shaped charge comprising a ring of high explosive formed by the revolution about a central axis of symmetry of first and second parallel lines making an acute angle with said central axis, there being a cavity in the forward end of said explosive formed by the revolution of third and fourth lines diverging forwardly at an acute angle with respect to each other from a point midway between said first and second parallel lines, each said diverging lines intersecting a respective one of said first and second lines at equal angles, and all said lines being coplanar at the points of intersection, the bisector of the angle between said third and fourth lines being inclined to and intersecting said longitudinal axis at a predetermined stand-01f distance forwardly of said charge, an inert packing material filling the conical cavity formed about said longitudinal axis by the revolution of the one of said first and second lines nearest thereto, and a generally conical shaped detonator symmetric with respect to said longitudinal axis and extending over the rearward end of said charge, for substantial simultaneous detonation of all parts of said ring of explosive.

2. A shaped charge unit comprising a first and second ring of high explosive concentrically about a central axis of symmetry, said first ring being formed by the revolution about said central axis of a first pair of parallel lines making a first acute angle with said central axis, said second ring being formed by the revolution about said central axis of a second pair of parallel lines making a second acute angle with said central axis, said second acute angle being greater than said first acute angle, a first cavity formed in the forward end of said first ring by the revolution of a first pair of forwardly diverging lines intersecting at a point midway between said first pair of parallel lines, a second cavity formed in the forward end of said second ring by the revolution of a second pair of forwardly diverging lines intersecting at a point midway between said second pair of parallel lines, said first and second pairs of forwardly diverging lines forming an acute angle therebetween, the bisectors of the acute angles formed by said first and second pair of diverging lines intersecting said central axis at a point forwardly of said unit, an inert packing material filling the conical cavities formed between said first and second ring and about said central axis by the revolution of the one of said first pair of parallel lines nearest thereto, and a generally conical shaped detonator symmetric with respect to said longitudinal axis and extending over the rearward ends of said first and second rings of explosive for substantially simultaneous detonation of said first and second ring.

References Cited in the file of this patent UNITED STATES PATENTS 2,407,093 Mohaupt Sept. 3, 1946 2,494,256 Muskat et al Jan. 10, 1950 2,506,836 Kaltenberger May 9, 1950 2,513,233 Byers June 27, 1950 2,587,243 Sweetman Feb. 26, 1952 FOREIGN PATENTS 369,237 Italy Mar. 15, 1939 122,828 Sweden Sept. 21, 1948 610,106 Great Britain Oct. 12, 1948 618,617 Great Britain Feb. 24, 1949

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