GB2228786A

GB2228786A - A safety device of a projectile fuze

Info

Publication number: GB2228786A
Application number: GB9004689A
Authority: GB
Inventors: Wilhelm Furst; Hartmut Gessler; Werner Rudenauer
Original assignee: Diehl GmbH and Co
Current assignee: Diehl Verwaltungs Stiftung
Priority date: 1989-03-04
Filing date: 1990-03-02
Publication date: 1990-09-05
Anticipated expiration: 2010-03-02
Also published as: GB9004689D0; FR2643982A1; GB2228786B; DE3907006A1

Description

1 A SAFETY DEVICE OF A PROJECTILE FUZE The invention relates to a safety

device of a projectile fuze which initiates a detonation of the projectile after penetrating through a barrier.

Such a safety device is used in the case of munitions which, prior to detonation, are intended to penetrate a roof ing or a wall. In accordance with the prior art, used as safety device are pyrotechnical delayed-action compositions or electronic delay circuits, which are started up by the impact on the barrier and after a specific time lead to the detonation. What is disadvantageous in this respect is the fact that the detonation is effected after a fixed time without taking into account the respective projectile velocity and the design of the barrier. The projectile therefore detonates too early or too late.

Described in DE-OS 34 18 759 is a safety device which works with a safety securing element which is movable transversely to the flight direction. This safety device is, however, not suitable for initiating a detonation of the projectile only after the penetration of a barrier.

An object of the invention is to propose a safety device, of the type mentioned at the beginning hereof, in 2 the case of which the instant of the detonation depends on the impact velocity of the projectile and the severity of the delay which the barrier exercises on the projectile.

In accordance with the invention the above problem is solved, in the case of a safety device of the kind mentioned at the beginning hereof, in that a springloaded element which is movable transversely to the flight direction is locked in a blocking position by a release member which is displaceable in the flight direction, in that the deceleration of the projectile which occurs as a result of the penetration of the barrier brings the release member into a position in which it releases the transversely movable element, and in that during or towards the end of the deceleration the transversely movable element goes into a detonation position.

If the deceleration lasts for a comparatively long time, because the barrier is thick and/or the impact velocity of the projectile against the barrier is small, then the detonation is effected later after the impact than in the reverse case in which the barrier is less thick and/or the impact velocity of the projectile is high. It is thus avoided that the projectile detonates while it is penetrating the barrier. The detonation is effected when the projectile flight is no longer 1 i i i i 1 1 1 i i i i 1 1 i 1 i i i i 1 i i 1 i i 1 1 3 decelerated, i.e. delayed, by the barrier, the projectile has thus penetrated through the barrier.

In the case of a development of the invention the transversely movable element is as a result of the deceleration of the projectile held in a friction-locking manner in a guide and initiates the detonation after conclusion of the deceleration.

In the case of another development of the invention the transversely movable element in the detonation position frees the release member in such a way that this initiates the detonation after completion of the deceleration.

is The invention includes a fuze and a projectile incorporating the safety device.

Further advantageous developments of the invention will become apparent from the following description of exemplified embodiments shown diagrammatically in the accompanying sectional drawings, wherein:-

FIGURE 1 shows a first exemplified embodiment of the 25 invention diagrammatically, FIGURE 2 shows a variation of the first exemplified embodiment, 4 FIGURE 3 to FIGURE 6 show a second exemplified embodiment of the invention diagrammatically in its various functional positions.

The mechanical safety device comprises a slider 2 which is arranged as transversely movable element in a fuze 1 of a projectile. Instead of the slider 2 a rotor could be provided. The slider 2 is mounted in the fuze 1 on a guide 3 so as to be displaceable in the direction R 10 transversely to the flight direction F of the projectile. The slider 2 is loaded by a compression spring 4.

Associated with the slider 2 is a release member 5 which is displaceable in the flight direction F and stands under the action of a compression spring 6 on a first step 7 of the slider 2. A second step 8 is linked to the first step 7 by a riser edge 15.

Prior to the launching of the projectile the slider 2 is locked by a blocking member 9. Arranged in the slider 2 is a detonator 10 which can be brought into a first detonation chain 11 and a second detonation chain 12. The first detonation chain 11 can be detonated by, for example, a proximity sensor. Associated with the second detonation chain 12 is a firing pin 13, which can be freed by the slider 2 by way of a release element 14.

The mode of operation of the described device in i 1 i 1 1 i 1 1 1 i 1 1 i i i i accordance with FIGURE 1 is generally as follows:

Upon the launching of the projectile the blocking member 9 frees the slider 2, so that this is displaced by the compression spring 4 in the direction R, until the release member 5 strikes against the riser edge 15 of the first step 7. The detonator 10 now stands in the first detonation chain 11. If a proximity detonation is desired, then the proximity sensor responds at a suitable distance.

if the projectile strikes a barrier, then the projectile is decelerated. In this way the release member 5 is shifted on account of its inertia contrary to the force of the compression spring 6 in the flight direction F. It is remains during the delay at the level of the second step 8. During the delay the slider 2 is forced against the guide 3, so that it is held in f riction- locking manner against this. When the barrier has been penetrated, the delay and deceleration end and the slider is further shifted by means of the compression spring 4 in the direction R, until the release member 5 strikes against a riser edge 16 of the second step 8. The detonator 10 now stands in the second detonation chain 12 and the release element 14 frees the firing pin 13. The detonation of the projectile. is thus effected after the penetration of the barrier.

i 1 6 In the case of the exemplified embodiment in accordance with FIGURE 2, instead of two detonation chains one detonation chain is provided. Accordingly two detonators 10 are arranged in the slider 2. An ignition means 17 of the detonation chain can be ignited by a proximity sensor or after penetration of the barrier by the slider 2 moving to close an electrical switch having contacts 18.

In the case of the exemplified embodiment in accordance with FIGURES 3 to 6 the component parts corresponding to the above description are provided with the same reference numbers.

In FIGURE 3 the device is shown in the flight phase of the projectile. A rotor 19 receives the detonator 10 and has swung this into the detonation chain 12. The blocking member 9 is arranged in the rotor 19 and has released the latter. prior to the launching, the rotor 19 was locked by the blocking member 9 in the fuze 1, and a pin 20 and ball 21 locked the blocking member. As a result of the launching acceleration this locking has been released to allow the rotor to be swung from a safe position into a ready position.

In the flight phase (see FIGURE 3) the release member 5 stands with a pin 22 in a bore 23 of the slider 2, so that the slider 2 cannot be moved in the direction i i i i i 1 7 by the f orce of the compression spring 4. A ball 24 (which prior to the rotation of the rotor 19, was held by the rotor to engage into a recess 25 of the release member 5, so that the release member was held nondisplaceably) has entered into the rotor 19, so that it no longer secures the release member 5 against a movement in the direction F.

The release member 5 has a collar 26 which forces a ball, provided as release element 14, into a recess 27 of the firing pin 13.

If the projectile strikes against a barrier, then the release member 5 is shifted under the action of its inertia against the force of the compression spring 6. The pin 22 thus leaves the bore 23 of the slider 2. The firing pin 13 continues to remain blocked (see FIGURE 4).

During the penetration of the barrier the slider 2 is displaced in the direction R by the compression spring 4 until a further bore 28 of the slider 2, the diameter of which is considerably larger than that of the bore 23, lies in the path of movement of the release member 5 (see FIGURE 5).

When the projectile has penetrated the barrier, then the deceleration of the projectile ends, so that the compression spring 6 now displaces the release member 5 p 8 contrary to the flight direction F. The release member 5 passes through the bore 28 of the slider 2. The collar 26 of the release member 5 thus leaves the ball 14. so that the f iring pin 13 now becomes free and under the action of a compression spring 29 strikes against the ignition means of the detonation chain 12. The projectile detonates (see FIGURE 6).

The invention is not confined to details of the foregoing examples and many variations and modifications are possible within the scope of the invention as defined by the appended claims. For example, the second embodiment may be adapted for electrical ignition of the ignition means 17 by omitting the firing pin and arranging for part of the member 5, e. g. the pin 22, to close a switch as it moves to the condition shown in FIGURE 6.

t 1 i 1 1 1 i 1 i i i i i 9

Claims

1. A safety device of a projectile fuze which initiates a detonation of the projectile after the penetration of a barrier, characterised in that a spring-loaded element which is movable transversely to the flight direction is locked in a blocking position by a release member which is displaceable in the flight direction, in that the deceleration of the projectile which occurs as a result of the penetration of the barrier brings the release member into a position in which it frees the transversely movable element, and in that during, or towards the end of, the deceleration the transversely movable element goes into a detonating position.

is

2. A safety device as claimed in Claim 1, characterised in that the transversely movable element as a result of the deceleration of the projectile is held by friction in a guide, and in that after conclusion of the deceleration the transversely movable element triggers the detonation.

3. A safety device as claimed in Claim 2, characterised in that a detonator is mounted in the transversely movable element, and in that the transversely movable element 2 upon its transverse movement brings the detonator into a detonation chain and triggers the detonation thereof.

1 i i i

4. A safety device as claimed in Claim 2 or 3, characterised in that the transversely movable element has an edge which strikes against the release member, and in that the release member is moved by the deceleration to leave the edge.

5. A safety device as claimed in any one of claims 2 to 4, characterised in that the transversely movable element is a rotor or slider which is freed in response to the launching acceleration of a projectile.

6. A safety device as claimed in Claim 1, characterised in that the transversely movable element in the detonating position frees the release member in such a way that this triggers the detonation after the conclusion of the deceleration.

7. A safety device as claimed in Claim 6, characterised in that the transversely movable element has a first bore into which the release member engages prior to the deceleration and thereby holds the transversely movable element in its blocking position.

8. A safety device as claimed in Claim 7, characterised in that the transversely movable element has a further bore through which the release member fits, which further bore lies in the path of movement of the release member when the transversely movable element detonation i i 1 i 1 1 1 i I i 11 position.

9. A safety device as claimed in any one of Claims 6 to 8, characterised in that the transversely movable element 5 is a slider or rotor.

10. A safety device as claimed in any one of the preceding claims, characterised in that a compression spring shifts the release member after the deceleration.

11. A safety device as claimed in Claim 1 wherein movement of the transversely movable element into the detonating position releases a f iring pin or closes a switch to effect detonation, and wherein the transversely movable element is mechanically returned during deceleration into the detonating position.

12. A safety device as claimed in Claim 1 wherein movement of the transversely movable element into the detonating position frees the release member to be moved by a spring contrary to the flight direction upon cessation of deceleration to release a f iring pin or to close a switch to effect detonation.

13. A safety device substantially as hereinbefore described with reference to FIGURE 1, FIGURE 2 or FIGURES 3 to 6 of the accompanying drawings.

12 1 1 i

14. A fuze or a projectile comprising a safety device as claimed in any preceding claim.

i i i 1 1 i i i i i Published 1990 atThe PatentOffice. StateHouse. 6671 ffigh H:)lbnrn.3, ondon WC1R4TP.Purther copiesmaybe obtainedfrom The Patent Otlice.

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