FR2624630A1 - DEVICE FOR ALIGNING A CHAIN OF ELEMENTS, PARTICULARLY APPLICABLE TO A PYROTECHNIC CHAIN - Google Patents

Abstract

The object of the invention is a device which, inserted in a chain of aligned elements, ensures the misalignment of this chain as well as, on command, its realignment. It mainly comprises: - a threaded pinion 2; - a screw 10, screwed into the pinion; - A barrel 3 comprising a bore 31 in which the pinion is engaged and carrying an element 51 to be aligned on an axis 53; a toothed sector 4 having the same axis as the barrel and integral with the latter, cooperating with the pinion to block the rotation of the pinion as long as the latter is engaged in the barrel, and driven by the pinion with a rotational movement when the pinion is released from the barrel. The control of the rotation of the screw results in a translation of the pinion until it is released from the barrel, then a rotation of the barrel ensuring the alignment of the element 51 on a predefined axis 53.

Description

DEVICE FOR ALIGNING A CHAIN

OF ELEMENTS, IN PARTICULAR APPLICABLE

A PYROTECHNIC CHAIN

  The present invention relates to a device which, inserted into a chain of functionally aligned elements, ensures the misalignment of this chain - as well as, on command, its realignment; Such a device is particularly usable to ensure the security in a system of initiation of a

i 0 explosive charge.

  Indeed, an explosive charge is generally equipped with an initiation system that allows controlled detonation, at the time and under the conditions - wanted, the lexplosive. The initiation systems are usually constituted by weak explosive charges arranged in cascade, or chain an electrical or mechanical device allows to initiate a detonator, which transmits its detonation to a series of pyrotechnic elements of increasing powers, such as that relay and

  impellers before initiating the explosive charge.

  The initiation system is called "armed" when. it is ready to detonate the explosive charge, that is to say when all its elements are in the required positions or are released to be able to take them, for

  that the system can operate in the intended mode.

  To avoid accidental initiation during handling, transport or fire operations, the pyrotechnic chain is interrupted, for example by misalignment of one of its elements, so that if the detonator comes to detonate, the premature explosion of the explosive charge either

avoided.

  The means known to cause the arming of an initiation system generally use a stored energy, electrical or mechanical, which may deteriorate or be released in case of prolonged storage, especially in atmospheres

  severe climatic or vibratory conditions.

  The subject of the present invention is an alignment device which, when applied to an initiation system for explosive loading, makes it possible to avoid

previous disadvantages.

  For this purpose, it comprises mainly - a threaded pinion - a screw, screwed into the pinion - a cylinder whose axis of rotation is substantially parallel to that of the pinion, having a bore in which is engaged the pinion and carrying the element to realign; - Means having the same axis as the barrel and i integral with the latter, cooperating with the pinion to: * block the rotation of the pinion and consequently the barrel as the pinion is engaged in the barrel * confer the barrel, which they are integral, a rotational movement under the action of the pinion, when this

the last is clear of the barrel.

  The application of a rotational movement to the screw then allows a translation of the pinion until its release from the barrel and, in a second phase, a rotation of the barrel

  likely to ensure the desired alignment.

  Other objects, particularities and results of

  the invention will emerge from the following description given to

  As a nonlimiting example and illustrated by the appended drawings, which represent: FIG. embodiment of the alignment device according to the invention - Figure 2, the illustration of a variant of

  realization of the previous figure.

  In these different figures, the same references are

relate to the same elements.

  FIG. 1 thus represents a method for realizing the

  alignment device according to the invention.

  In this figure, there is shown an axis 1, called input axis, extending by a threaded portion 10 forming a screw, the axis 1 being rotatable about a longitudinal axis 12. The axis i is carried by example by a 'frame 13

  through a piece 11 forming a stop.

  The device also comprises a toothed gear 2

  whose interior is threaded to receive the screw 10.

  The device further comprises a barrel 3, substantially disk-shaped, rotatable about an axis 40, substantially parallel to the axis 12 and passing through the center of the disc. The barrel 3 comprises a bore 31, not coaxial with its axis of rotation 40, in which the pinion 2 is inserted. The device further comprises means 4, capable of cooperating with the pinion 2, such as a toothed disk at least on a portion of its periphery, forming a sector, as shown in FIG. Sector 4 even

  axis (40) that the barrel 3 and it is integral with the latter.

  The device further comprises a detonator 50, carried by a not shown frame, and a relay 54 carried by a frame 14, located on the same axis 53 as the detonator 50. The elements and 54 are arranged so that they are separate by the barrel 3. The latter still carries a relay 51, intended to be aligned, on command, by the device according to the invention,

  with the elements 50 and 54 on the axis 53.

  The operation of this device is as follows: In the figure, the various components are shown in their initial, non-aligned position. In this position, the barrel 3 serves as a mask between detonator 50 and

the relay 54.

  When a rotational movement is imparted to the input shaft 1, which movement constitutes the realignment control, the screw 10 provokes by turning the translation (arrow 20) of the pinion 2. Indeed, the sector 4 cooperating with the teeth of the pinion blocks the latter in rotation as the pinion is engaged in the bore 31 of the barrel 3. The translation movement of the pinion 2 continues until the latter is released from the barrel 3 and abuts on 11. At this time, the pinion is more driven in rotation, causing that of the sector 4 and, consequently, that of the cylinder 3. The total rotation angle of the cylinder is of course depending on the part sector 4 which is toothed, and the initial position of the latter on the pinion 2. In the final phase, the pinion 2 escapes the toothed sector 4 and allows the input shaft 1 to continue to rotate; this allows Axis 1 to carry out possible other

  functions without altering the alignment of the priming system.

  The effect of the rotation is represented by dotted arrows on the barrel 3: the relay 51 then aligns (dashed trace 52) on the axis 53 with the elements 50 and 54, thus realigning the pyrotechnic chain 50, 51 , and 54

  on the axis 53, the latter then being ready for operation.

  In the configuration of FIG. 1, when the power of the detonator 50 is sufficient, the relay 51 can be replaced by a single orifice, allowing the

detonation.

  It should be noted that the rotation time of the pinion is practically negligible compared to its translation time, the latter thus substantially representing the alignment time of

chain.

  FIG. 1 also shows various locking and safety devices that can be used one or the other or in combination in the device

according to the invention.

  Thus, the rotation of the barrel 3 allows a spring 74, stored in the free state, to store energy which, partially restored, serves to lock the cylinder in the aligned position, thanks to a suitable notch 33 to receive a locking finger 73, allowing the locking of the barrel 3

  in a position corresponding to the desired alignment.

  There is also shown a finger 71, carried by the frame 14, being inserted into a notch 32 of the barrel 3. This finger constitutes a locking device that can be

  unlocked under the action of an acceleration.

  Another locking device is shown in the form of a finger 72, coming to press the screw at the pinion 2, intended to prevent any translational movement of the latter. This finger is used. for example to ensure the safety of the device during storage and

  it is removed during use.

  In an alternative embodiment also shown in Figure 1, this structure can be used to realign a second pyrotechnic chain: the barrel 3 then comprises a percussion detonator 61, arranged to be brought into alignment with the axis 12 during the rotation of the barrel. The device then comprises, in addition, worn by

  example by the frame 14 and aligned on the axis 12, a relay 62.

  This chain is then initiated by the percussion of the pinion 2 or the screw 10 on the detonator 61 when for example the impact of the projectile. More generally, the system according to the invention allows the alignment of a second chain of elements, or a third chain or a neme chain, each of the chains not necessarily being initiated by the same principle. (a

  percussion in the previous example).

  In the case where such a device is used in a projectile, the explosive charge is for example disposed behind the frame 14, in contact with the relay 54. In the same-type of application, the realignment control, that is, that is to say the rotation of the shaft 1, for example provided by a turbo-alternator, also ensuring the electrical supply of the projectile, set in motion by the projectile on its trajectory, and this, possibly via a

  reduction system or angular velocity multiplier.

  FIG. 2 represents a variant embodiment of

device according to the invention.

  In this figure, the detonator 50 and the relay 51 have been replaced respectively by a detonator 56 and a flange 55.

for the power supply.

  In addition, it is not represented the variant of making a second chain, using the elements 61 and 62 of Figure 1, nor the different safety devices

  and locking 71 to 73 of Figure 1.

  The operation of this device is similar to the previous one: the rotation of the barrel 3 causes the alignment on the axis 53 of the elements 55, 56 and 54; in this way, the detonator 56, aligned with the relay 54, is capable of receiving the electrical energy necessary for its detonation by

through the flange 55.

Claims (8)

  1. A device for aligning a member with a chain of elements on command, characterized in that it comprises - a threaded pinion (2) - a screw (10), screwed into the pinion - a barrel (3 ) whose axis of rotation (40) is substantially parallel to that of the pinion, having a bore (31) in which the pinion may be engaged and carrying the element (51) to be aligned; 1 0 - means (4) having the same axis as the barrel and integral with the latter, cooperating with the pinion to: * block the rotation of the pinion when the latter is engaged in the barrel * impart to the cylinder a rotational movement under the action of the pinion, when the latter is released from the barrel; the control being constituted by the application of a rotational movement to the screw, which has the effect of a translation of the pinion until its release from the barrel and then, in a second phase, a rotation of the barrel can thus ensure the desired alignment.   2. Device according to claim 1, characterized in that the means (4) ensure the free rotation of the screw (10) after the second phase.   3. Device according to claim 1, characterized in that the means (4) comprise a toothed sector,   whose teeth cooperate with the teeth of the pinion.   4. Device according to one of the claims   preceding, characterized in that it further comprises   means forming an abutment (11) for the pinion (2).   5. Device according to one of the claims   previous, characterized by the fact that the barrel (3) carries a plurality of elements, its movement allowing the alignment of the latter respectively with a plurality of chains of elements.   6. Device according to one of the claims   characterized in that it further comprises means (71-73) for locking the movement of one or many of its components.   7. Application of the device according to one of the   preceding claims to a projectile comprising a rocket,   characterized by the fact that said chain is a chain pyrotechnic forming the rocket.   8. Application according to claim 7, characterized in that the projectile comprises a turbo alternator and that the rotational movement is supplied to the screw by the rotation of the turbo-alternator shaft.