FR2616530A1 - GUIDE WIRE COIL FOR MISSILES - Google Patents

Abstract

The invention relates to a missile guidewire spool, which consists of a winding of a guidewire on a spool body which is placed at the rear of the casing 10 of the missile, the rear part 11 of the missile. 'casing 10 of the missile being made to rotate in order to considerably reduce the unwinding forces, so that the guide wire 12 unwinds parallel to the axis of the missile and without resting in the form of a loop against the inner wall of the casing 10 .

Description

The present invention relates to a guide wire coil for missiles.

  guide wire coil for missiles, consisting of a coil of a guide wire on a coil body which is placed

  on the back of the missile shell.

  Coils of guide wire of this type have already been described in various forms, in particular by the applicant. They equip the guided missiles, the guide wire having to be unwound without obstacle

  at a speed of up to approximately 300 m / s.

  The guide wire is most often a copper conductor reinforced by carrier wires or an optical fiber also reinforced; steel wires have however also already been used. During the entire flight phase, this guide wire must transmit

  control pulses without significant damping.

  In the known embodiments, the guide wire is removed axially from the spool during the unwinding, that is to say that the turns during the unwinding effect, depending on the diameter of the spool, up to 60,000 revolutions / minute around the longitudinal axis

of the coil.

  When unwinding the guide wire spools, inertial forces, aerodynamic forces and

  friction forces act on the guide wire.

  The solicitation of the latter by the forces of friction

  This increases sharply with higher wire feed speeds, as shown in the diagram in Figure 4. It is shown that although the extraction speed remains constant after acceleration, the reaction forces increase, since d on the one hand the angular speed of the turns of the guide wire unwinding in a helical manner increases when the diameter of the coil decreases and that on the other hand, the length of the layers also increases as the

shows figure 1.

  The object of the invention is to create a guide wire coil for missiles of the type initially mentioned.

  in which the significant reaction forces ap-

  appearing from the fact that the guide wire being unwound rests in the form of a loop against the

  inner wall of the missile shell are removed

  so that unreinforced optical fibers

  These can now be used as a guide wire. This objective is achieved in that the rear part of the missile envelope is made rotary and the rotational force is produced by the moment of friction of the guide wire during reeling

or by moving air.

  According to developments of the invention: - the coil carries a guide wire constituted by an unreinforced optical fiber wound in a balloon and is supported by a rotary body mounted at reduced friction; - the rotating rear part of the missile envelope is also provided with increasing air guiding means

the rotation.

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  1 It is now necessary to describe an example of implementation using the drawings, in which: FIG. 1 represents a side view of a coil

  guidewire in accordance with prior art

  laughing with a guide wire of which

  the turns are unwound helically-

  the, Figure 2 shows a perspective view in partial section of a guide wire coil according to the prior art in which the guide wire ball rests in a loop against the inner wall of the missile envelope ,

  Figure 3 shows a cross section of a

  rotary missile veloppel with a coil

  incorporated with guide wire according to the invention

tion,

  FIG. 4 represents a diagram of the forces of friction

  separation and separation when extracting the guide wire from a coil in accordance

to the prior art.

  The embodiment of FIG. 3 of a guide wire coil for low friction missiles operating with considerably reduced unwinding forces shows that the rear part 11 of the missile envelope is made to rotate and that the rotational force is produced by the moment of friction of the guide wire 12 during unwinding or by the moving air. The coil 13 carries for this purpose a guide wire 12 consisting of an unreinforced optical fiber wound in a balloon and is supported by a rotary body mounted at reduced friction and composed of a coil support 14 and a centering ring 15 1 housing a ball bearing or a rolling bearing 16. The rear part 11 of the envelope 10 of the missile

  rotate around this device.

  This configuration makes it possible to avoid that, when the unwinding speed increases, the balloon or the coil of guide wire 12 rests in the form of a loop against

  the inner wall of the missile shell and provo-

  that thus too high reaction forces, like

  this is shown schematically in Figure 2.

  Because of these forces, it was necessary, when using optical fibers, to provide them with a special reinforcement. The measures described above however considerably reduce the tensile force in the guide wire and therefore make it possible to use unreinforced optical fibers which not only reduces the work and the manufacturing costs, but also allows

  significantly increase the range of missiles.

  In the ideal case, the rear part 11 rotates at the angular speed w = v / rv being the wire feed speed and r the radius of the spool, so that the guide wire 12 is drawn from the envelope 10 of the missile parallel to the axis

longitudinal of the coil.

  The rotation of the rear part 11 of the missile envelope can be caused on the one hand by the moment of friction of the guide wire 12 in progress

  and on the other hand by the moving air.

  In a particular embodiment, it is planned to further provide the rear part 11 with means

  air guide (not shown) increasing the rotation

  tion. These can easily be placed

2,616,530

  1 afterwards in the form of a ring of plastic material

  that subsequently mounted on the missile envelope and comprising small guide vanes, etc.

Claims (3)

  1 1. Guide wire coil for missiles, consisting of a winding of a guide wire on a coil body which is placed at the rear of the missile casing, characterized in that the rear part (11 ) of the envelope (10) of the missile is made rotatable and the rotational force is produced by the moment of friction of the guide wire (12) in progress   or by moving air.   2. Guide wire coil for missiles according to claim 1, characterized in that the coil (13) carries a guide wire (12) constituted by an unreinforced optical fiber wound in a balloon and is supported by a rotary body (14 , 15) mounted with reduced friction.   3. Coil of guide wire for missiles according to claim 1 or 2, characterized in that the rotary rear part (11) of the envelope (10) of the missile is further provided with increasing air guiding means the rotation.