US3430564A - Explosive gate,diode and switch - Google Patents

Description

March 4, 1969 D. A. SILVIA ET AL 3,430,564

, EXPLOSIVE GATE, DIODE AND SWITCH Filed May :3, 1967 Sheet of z FIG. 1 FIG. 2 20' INVENTORS Den/s A. .Si/w'a Richard 7. Ramsey John H. encer BY M f nrronun W M4 our March 4, 1969 D. A. SILVIA ETAL 3,430,564

EXPLOSIVE GATE, DIODE AND SWITCH Filed May a, 1967 Sheet 2 of 2 L FIG. 6 6

70 MISS ILE SEPARA T/O/V 1' -MI I OUT PUTS 7'0 DEPLOYMENT CHARGES United States Patent 6 Claims ABSTRACT OF THE DISCLOSURE An improved, all secondary explosive, logic andswitching device in which a point contact from an explosive trail with a constricted region of the same or other explosive trail can produce a destructive cross-over, an explosive d1- ode switch or other logic operation.

Government interest in the invention The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

Cross-reference to related application This application is an improvement over pending application Ser. No. 478,676, filed June 30, 1965, now US. Patent No. 3,289,106 for Explosive Circuits, by Denis A. Silvia.

Background of the invention In the above referred to patent application, explosive circuit elements are disclosed, including the destructive crossover and the null gate, from which all the primary functions of binary logic can be constructed. The destructive crossover is formed by providing a pair of trails on the surface of an inert material which trails intersect at right angles and are filled with an explosive. Gaps are left at the intersection to provide a junction or island, such that, propagation through the leg of one trail, is strong enough to jump its gap and consume the explosive in the island, thereby preventing propagation from one to the other leg of the intersecting trail. The detonation proceeding along either trail is not strong enough, however, to turn the corner into either leg of the perpendicular trail. The null gate and other binary logic functions are constructecl as extensions of the basic destructive crossover. Although this system is workable and unlocks a new scope to explosive circuitry, dimensions of the trails and gaps are extremely critical and do not lend themselves readily to easy manufacture. The reliability of this system also remains in doubt due to these factors.

Summary of the invention The instant invention is concerned primarily with an improved explosive circuit and, in particular, with an explosive diode and an explosive nulling gate from which an integrated circuit can be constructed paralleling their electronic counterparts. The criticality of the trails and gaps as above-noted, has been substantially avoided since this invention involves the use of no gaps. The present improvement instead provides for a trail having a necked down or notched portion along its length and an intersecting trail terminating at a point and making a point contact with the notched area. Consumption of the explosive at the notch via the point contact prevents further propagation along the other trail. In like manner, an explosive diode is constructed wherein a single explosive trail is provided with a constricted area along one portion of its length and a point along another portion of its length "ice making a point contact with the constriction. Propagation in only one direction thereby results if the explosive is made to pass in a direction reaching the constricted area first. Propagation, therefore, continues to the end of the trail uninterrupted. However, if the direction of the explosive is such that the point is first reached, the constriction is consumed and further propagation through the trail is prevented. The nulling gate easily gives rise to the construction of an explosive switch and together with the explosive diode an explosive circuit may be provided. One such circuit contemplated uses merely two explosive inputs and yields five or more explosive outputs. Primary explosive is required only at the explosive inputs whereas secondary explosive is sufficient for-the circuitry itself, thereby requiring only two safe arming devices instead of five.

Brief description of the drawings FIG. 1 illustrates an explosive null gate according to the instant invention;

FIG. 2 illustrates an explosive diode according to the present invention;

FIG. 3 is the same diode as in FIG. 2 except that a more streamlined version is shown;

FIG. 4 is an elementary circuit involving two gates used to construct an explosive switch;

FIG. 5 illustrates a destructive crossover constructed from two explosive diodes and two explosive gates;

FIG. 6 is an explosive circuit according to the present invention illustrating the construction of five outputs from two sequenced inputs; and

FIG. 7 is an explosive circuit using the outputs from FIG. 6 for performing the firing operation of a specific warhead design.

Description of the preferred embodiments The explosive circuitry according to the afore-described related design is a sufficiently reliable system if extreme care is taken to construct the critical trail dimensions and gap spacings. In the interest of expediting production manufacture of miniature charges and in improving upon reliability, the ends of the trails in the related application were first sculpted to form miniature shaped charges. This modification significantly improved its reliability and largely eliminated crosstalk between intersecting legs of the null gate. A bonus was obtained in that the gate would propagate only in the direction of the shaped charge since such a charge is inherently unidirectional. Removal of the incoming trail from the gate and the junction between trails produced a diode since the gap could be crossed only in the forward direction of the shaped charge. This system was found to work quite reliably but the gap dimensions were still somewhat critical and the fabrication tedious. Need for elimination of the critical gap led to the instant invention of which FIG. 1 illustrates a plate 10 of inert material with an explosive trail B and an explosive trail A provided thereon. These trails may be constructed by forming a channel or grooves in plate 10 and filling them with an explosive, such as Du Pont EL506C, or, by fabricating the trails using the Du Pont sheet explosive. The null gate of FIG. 1 is a simple explosive switch which performs the function of disrupting an explosive trail.

. The null gate can be used to form an explosive diode as well as other explosive elements such as the selective switch, all of which will be hereinafter described.

In FIG. 1, if a detonation proceeds along explosive trail B in either direction, it will normally pass through the constricted region 12, formed by notch 11, and emerge out the other side of the trail. If, however, a detonation on trail A arrives at the constricted area 12 by approximately one microsecond before the detonation on trail B passes therethrough, then the constriction at 12 is destroyed or consumed and further detonation on trail B will be prevented. As can be seen from the drawings, the trail A terminates at a point 13 and is designed to make a loose contact with the explosive trail B. In this manner, only the explosive at 12 is destroyed without the remainder of trail B being affected. The success of the operation depends on the combined effect of several factors. For example, the explosive width at constriction 12 must be less than the minimum thickness for sustained detonation. Thus, the detonation is dying while passing through 12. The length of area 12 must also be short enough that sustained detonation is rapidly recovered after passing therethrough. Because the detonation is dying in 12, it is thereby easily stopped by breaking from explosive trail A. Also, the narrowing of trail A as at 13 must be such that it induces a dying detonation in the trail, and a destruction at the restricted area 12. In addition, the loose contact with area 12 at point 13 makes transfer of detonation from A to B more difiicult. As a result, the destruction of area 12 is efiected from the sides 14 of trail A, directly blasting in a dispersing manner away from point 13 to fully destroy the explosive at the constricted area. Finally, by notching the side of trail B at 11, directly opposite from trail A, a minimum amount of explosive trail B is exposed to blast from trail A. Since all of these factors supplement each other, considerable slack is allowable in any one of them leaving reliable operation of the device still capable of being achieved.

In FIG. 2 of the drawings, a plate 20 of inert material is provided with an explosive trail C, D, E, F, G on its surface in the same manner as the explosive trails on plate 10. An explosive diode is constructed in accordance with the null gate of FIG. 1 in such a way that it will propagate detonation in only one direction as shown by the arrow. A more sophisticated and more compact approach to the construction of an explosive diode is shown in FIG. 3. It is the same in all other respects to the FIG. 2 diode. In FIG. 3, a plate 30 of inert material is provided on its surface with an explosive trail C, C, E, F, G in the configuration shown and constructed according to the manner suggested with regard to trails A and B of FIG. 1. As shown in FIGS. 2 and 3, an explosive diode is constructed which is a one-piece, all secondary explosive, significantly smaller and easier to make diode, simply by using a self-gating explosive trail. A detonation proceeding along the trail from G to C in FIG. 2 or from G to C in FIG. 3, encounters no difficulty in being transmitted. On the other hand, when a detonation commences from C, FIG. 2, or C, FIG. 3, circumstances are entirely different. In FIG. 2, the detonation from C splits into two parts. One part trying to take the long path through E while the other takes the short path through D. Since the path through D arrives at the constriction 12 first, it destroys the constriction and prevents the detonation, by way of E, from ever reaching F or G. The diode in FIG. 3 operates in a like manner, i.e., a split of the detonation from C into two parts; one part trying to take the long path through E while the other takes the short path through D. Since the path through D arrives first at the constriction 12 through point 13, it destroys the constriction and prevents the detonation by way of E from ever reaching F or G. The arrow in FIG. 3 shows the direction of allowable propagation through the diode.

By using two null gates in accordance with FIG. 1, a selective switch can be constructed as shown in FIG. 4. The trails are constructed on inert plate 40 according to the manner hereinbefore described, and in the configuration as shown. If detonation occurs on trail A, before detonation occurs on trail B, trail A-B will be cut-ofi by the null gate at 41 and the detonation will propagate along A-B to the output. If, however, detonation occurs on trail B before detonation on trail A, then trail A-E will be cut at the null gate 42 and detonation will then propagate on trail A-B since the null gate 41 cannot prevent propagation therealong.

In FIG. 5, a pair of explosive diodes and a pair of explosive null gates are used to construct a destructive crossover. A plate 50 of inert material is provided with trails between H and H and between I and T configured as shown and constructed according to the hereinabove teachings. Propagation commencing at H is transmitted through diode 51 after which it splits into three paths; one toward H another toward K and a third toward L. The path to K subsequently splits into two parts; one toward the null gate 53, the other toward diode 52. The diode at 52 prevents further detonation therethrough. The null gate at 53 fails to prevent propagation toward H since the explosive has already passed therethrough. Propagation through L, on the other hand, arrives at null gate 54 subsequent to propagation through M whereby continued transmission through gate 54 is thereby prevented. Uninterrupted transmission of the explosive from H to H is accordingly provided. Propagation commencing at I is transmitted toward T in a like manner. As it passes through diode 52, it is split into two parts; one to N, the other to K. N activates null gate 53 such that K, in subsequently splitting off towards gate 53, is prevented from being transmitted therethrough. Diode 51 prevents K from continuing its propagation t H so K continues on toward L which passes uninterrupted through null gate 54 and to T Obviously, M has not been detonated because of N activating null gate 53. M therefore fails to activate gate 54 and permits L to continue therethrough.

Several applications of explosive circuitry have been considered. One which has received serious attention is the 5 for 2 circuit. In this circuit, two inputs are comlined, and, with a subsequent logical separation of the signal, through the use of switches, up to five separate outputs are yielded. The circuit is depicted in FIG. 6 in which four explosive switches and two explosive diodes are used with delays regulated by path length. The circuit as given uses the input I only (I), II only (II), I and II, simultaneously (I, II), I followed by II (I II) and II followed by I (II I). More outputs could be provided by using more than one delay time between I and II for the I II and II I options, thus using two additional switches and delay elements and providing two more outputs. The circuit herein giving five outputs from two inputs uses the FIG. 3 type diodes and the FIG. 4 type switches described hereinabove. The explosive circuit of FIG. 6 is printed onto a plate 60 of inert material in the same manner as in the above-described figures and in the configuration as shown by the drawing. Initiation of either I or II will start detonation on T but the diodes 65, 66 prevent back detonation toward I or II, respectively.

Upon detonation of I, switch 61 causes detonation to continue along T because of the time delay at D Switches '63 and 64 will allow propagation therethrough to output I since the paths to I, II and I II are respectively cut-01f by each switch. If II is detonated at the same time as I, switch 63 will cause the detonation at T to be switched to path T II and through to output I, II. This switching operation is assured because of the time delay of detonation I as it passes through D If detonation on II is subsequent to I; II will not arrive at switch 63 before detonation on T Detonation on T will continue therethrough, will be delayed at D; and be switched to output I II by switch 64. Since the detonation on T; arrives at switch '64 subsequent to the detonation on II due to the time delay at D propagation to output I is switched to output I II. If II is detonated first, unaccompanied by I, then the detonation at T will go through switch 61, to T after which switch 62 will cut-01f propagation to output II I and cause it to be switched to output II. If I is detonated subsequent to II, the detonation along I will reach switch 62 before the detonation along T because of the delay at D Such being the case, propagation to II will be cut-off whereupon switch 62 will cause propagation to continue toward output II I. In order to achieve the five outputs from the above-described explosive circuit, a simple variability in the functioning time of the detonators I, II must be made in the circuit. The delay time for detonation by an electric cap can be stated as die, where d is the average time and e is the maximum variation from average time of detonation. The circuit correction to take this into account is to place a small delay in trail T, as at D This delay should be of duration 2e. It then easily follows that D and D must be several times larger than 22 for proper functioning. For example, e being approximately one microsecond, is not difficult to obtain from a hot wire cap and, in this case, B; equals D equals ten microseconds would be an acceptable delay for operation of this circuit. The 5 for 2" circuit is then completed and may be used with two detonators to provide the equivalent of five detonators if a method of timing the two inputs is available.

The copending application Ser. No. 643,298, filed May 25, 1967, by Adams, may find specific application of the FIG. 6 type explosive circuit. There, a four sector warhead device can be explosively opened in such a way that it may be directed in any one of four directions, or detonated without opening, it so desired. This is performed by using four opening charges and appropriate delays in order to give the sectors time to deploy before detonating the main charges. Explosive circuits, according to the instant invention, may be used in order to reduce the number of delays necessary by first mixing the five inputs gathered from the five outputs of FIG. 6, to perform missile separation and delay functions. One signal is sent to the delay boosters while another is decoded to actuate the proper opening charge and deploy the warhead. One of the signals may bypass missile separation, the opening circuit and the deploy delay to give instantaneous isotropic detonation.

For a more complete understanding of this specific operation, reference to FIG. 7 is made. This circuit is constructed onto a plate 70 of inert material as in the other circuits and configured in the manner as shown. The five outputs from the FIG. 6 circuit become inputs to the FIG. 7 explosive circuit. Four of these inputs, when initiated, will deploy one of four hinge and cutting charges, depending on the position of the target. The fifth input, when activated, will bypass the deployment charges and detonate the entire warhead in a conventional manner. For example, in FIG. 7, the explosive trail at II bypasses missile separation, the opening circuit or deployment charges, and the deployment delay, and acts to initiate all four explosive boosters simultaneously for immediate detonation of the entire warhead. Initiation of I only will cause propagation of the explosive to split into two directions; one toward diode 71 and the other toward gate 77. The explosive gate at 77 is thereby closed and propagation through diode 71 is permitted until it splits off into two additional directions; one toward diode 74, the other toward gate 78. Diode 74 prevents further propagation and gate 78 is thereby closed. Propagation continues through diode 72 until it spilts off again into two more directions; one toward diode 75, the other toward gate 79. Diode 75, as in 74, prevents further propagation, and gate 79, as in gate diode 78, is thereby closed. Propagation continues further through diode 73 and is split into three direc tions; one being toward diode 76 which prevents further propagation, one toward the missile separation delay, and the other to missile separation to eifect a severance of the warhead from the missile. Propagation continues and is impeded at missile separation delay in order to give the warhead ample time to separate from the missile before proceeding to deployment of the hinge and cutting charge, which is the second step of the operation. Because explosive gates 79, 78 and 77 are closed, nothing will prevent propagation along the trail to deploy its proper hinge and cutting charge at output I. It should be noted that the explosive has been sufiiciently delayed at deployment delay while the second step of the explosive circuit is being carried out. As the explosive continues through deployment delay, it is split off toward each of four booster outputs for simultaneously exploding the four opened segments of the warhead. Should the I II sequenced explosive input as in FIG. 6 be initiated in the FIG. 7 circuit, propagation would proceed through diode 74 and be later split off into three directions; one toward diode 71, which prevents further propagation, one toward diode 72 and one toward gate 78, which thereby becomes closed. Propagation continues through diode 72 and is split oif again into three directions; one toward diode 75, which prevents further propagation, one toward diode 73 and one toward gate 79, which thereby becomes closed. As propagation continues through diode 73, it is again split up in three directions; one towards diode 76, which prevents further detonation, one to missile separation, which is the first phase of the warhead operation, and the third through missile separation delay. Here, propagation is sufficiently impeded before continuing through to deploy the hinge and cutting charge. As can be seen, gates 79, 78 are closed, whereby no interference arises in deploying the proper hinge and cutting charge at output I II. Also, gate 80 prevents propagation toward output I. Upon initiation of the I, II input, the explosive is propagated through diode 75 and splits oil in three directions; one toward diode 72, which prevents further propagation, one toward explosive gate 79, which thereby becomes closed, and one through diode 73. A three-direction splitoff is again caused; one toward diode 76, which prevents further propagation, one to missile separation and one to missile separation delay for the above-noted reason. Propagation to deploy the proper hinge and cutting charges at output I, II is made possible by the closing of gate 79. Gate 81 prevents propagation toward outputs I and I II. Lastly, if it were found necessary to initiate II- I, propagation would proceed through diode 76- and split into three directions; one toward diode 73, which prevents further propagation, another to missile separation and another to missile separation delay to again await complete separation of the warhead from the missile. As can be seen from the drawing, explosive gate 82 prevents propagation toward outputs I, I II or I, II. In each of the four cases, as the second step of the operation is completed, f ull deployment is awaited at deployment delay. Propagation thereafter continues and splits into four paths toward the booster outputs for detonating the four open segments of the warhead simultaneously.

Used throughout the several views of the instant in vention is a secondary explosive for the circuits. Since primary high explosive is not necessary, no safe arming is needed between it and other parts of the explosive trail. For example, in the FIG. 6 explosive circuit only two safe arming devices are required between the inputs at I and II and five outputs. The use of high explosive only at the two inputs eliminates three safe arming devices. As in the FIG. 6 configuration, this is obviously a drastic weight and space saving factor. In addition, the instant invention lends itself to a greater simplicity and ease of fabrication of the explosive gate, diode and switch, and, because of less critical dimensions, reliability of the new devices are much improved.

Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that Within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

What is claimed is:

1. An explosive logic device comprising:

a supporting plate of inert material having formed thereon a first explosive trail and a second explosive trail, said first trail having a constricted area along a portion of its length, said second trail terminating at a point and making a loose point contact with said first trail constricted area thereby forming an explosive null gate, whereby detonation proceeding along said first trail in either direction will pass through said first trail constricted area and emerge out the other side of said first trail if the explosive at said first trail constricted area has not already been destroyed by a detonation proceeding along said second trail.

2. The device of claim 1 wherein said first trail is notched along said portion of its length thereby forming said first trail constricted area.

3. The device of claim 2 being further characterized by a third explosive trail and a fourth explosive trail, said third trail communicating with said first trail at one side of said first trail constricted area and said fourth trail communicating with said first trail at the opposite side of said first trail constricted area, said third trail being notched along a portion of its length thereby forming a third trail constricted area, said fourth trail terminating at a point and making a loose point contact with said third trail constricted area and said first and second trails being in communication with each other, thereby forming an explosive switch, whereby detonation proceeding along said first trail will pass through said first trail constricted area and emerge out the other side of said first trail if both the explosive at said first trail constricted area has not already been destroyed by a detonation proceeding along said second trail, and, if the explosive at said third trail constricted area has been destroyed by a detonation proceeding along said fourth trail.

4. An explosive logic device comprising:

a supporting plate of inert material having formed thereon a continuous explosive trail having a constricted area along one portion of its length and an extension forming a point along another portion of its length, said point forming extension making a loose point contact with said continuous trail constricted area thereby forming an explosive diode, whereby detonation in one direction only is allowed along said continuous trail since said continuous trail constricted area will be destroyed, thereby preventing further propagation, if the detonation arrives first at said point forming extension.

5. The device according to claim 4 wherein said continuous trail is notched along said first portion of its length thereby forming said continuous trail constricted area.

6. An explosive circuit comprising:

a supporting plate of inert material;

two trails of secondary explosive material formed on said plate for receiving explosive inputs into the circuit;

two explosive diodes provided between said trails;

at least four explosive switches provided between said trails interconnected by paths filled with secondary explosive; and

time delays along said paths, whereby, activation either along one of said trails alone, the other of said trails alone, both of said trails simultaneously, said one of said trails before said other of said trails, or said other of said trails before said one of said trails, will produce at least five explosive outputs.

References Cited UNITED STATES PATENTS 3,095,812 7/1963 Coursen 102-27 3,175,491 3/1965 Robertson 102-27 3,311,055 3/1967 Stresau et al. 10222 3,368,485 2/1968 Klotz 102--27 VERLIN R. PENDEGRASS, Primary Examiner.

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