GB2175982A - Ignition apparatus - Google Patents

Abstract

An apparatus for optional ignition of at least two propulsive charges or gas generators 2,3 for the expulsion of projectiles or payloads 5 from tubes wherein the ignition can be individually, simultaneously or successively selected immediately before the ignition moment by a computer (14) determining the ignition sequence of the propulsive charges or gas generators and using an ignition switch element 10. The element 10 includes, for each propulsion charge to be ignited, a storage capacitor (18) and an ignition switch (20,21), the latter being connected to the said capacitor and actuated by a timing unit (19), whereby primer capsules 8,9 are ignited. The charges act via pistons 4 or themselves act as pistons, in which latter case line 13 to the computer is separated. Gas generator charges (32,33) may be situated away from the expulsion tubes and connected thereto by pipes. <IMAGE>

Description

SPECIFICATION Ignition apparatus for propulsive charges or gas generators The invention relates to an apparatus for ignition of propulsive charges or gas generators.

In DE 24 47 676 there is disclosed an apparatus which is described as a firing device for a projectile provided with a tubular tail boom. In this system a first propulsive charge of a larger size is provided on the outside of the tube, inside of which and on a level with a second propulsive charge is provided ignition channels which can be optionally opened or closed by a ring fitted around the outside of the tail tube. The second propulsive charge is only ignited by the first propulsive charge when the ignition channels are open. The projectile can thus achieve different ranges with different charge intensities. In this firing device the adjusting ring has to be set before the projectile is inserted into the weapon, and there is no means by which the second, larger propulsive charge can be ignited by itself or before the other charge.

An object of this invention is to make it possible for the respective propulsive charges to be optionally ignited separately, simultaneously or in succession, up to the point immediately before the moment of ignition.

According to this invention there is provided apparatus for the optional ignition of at least two propulsive charges or gas generators for the expulsion of projectiles or payloads from tubes, the apparatus having a computer to determine the ignition sequence of the propulsive charges or gas generators and an ignition switching element containing a timing unit connected to the computer with a storage capacitor for each propulsive charge and an ignition switch connected to the said capacitor and actuated by the timing unit, said switch serving to connect in circuit a primer capsule.

The invention enables the moments for the ignition of each propulsive charge to be determined at any time up to. shortly before the ignition instant and in accordance with the conditions and by means of the appropriately programmed computer which first of all effects the charging of the storage capacitors and then transmits to the timing unit the ignition pulses for closing the ignition switch for each of the said charges. In a preferred embodiment of the invention each ignition capacitor in the ignition switching element is preceded by a diode with a decoder being interposed between the computer and the timing unit.

The ignition apparatus according to the invention can be used for igniting propulsive charges or gas generators of any kind. In devices for the expulsion of projectiles or payloads wherein the propulsive charges are situated in the projectile tube or in the ejection tube the time switch element can be positioned together with the propulsive charges in the projectile or ejection tube while the computer is mounted outside them together with the operating elements. These systems offer considerable advantages in operation. For example, with mortars and sub-ammunition dispersion containers it is of a great advantage for the expulsion speed to be varied by optional ignition of one or more propulsive charges which do not have to be altered prior to the loading operation. In the case of mortars, aiming and readjustment in the elevation would then be unnecessary.In the case of sub-ammunition dispersion containers there would still be time at the last moment to adapt the distribution of the sub-ammunition to the configuration of the target, in order to save ammunition or increase the ammunition density per target element. Furthermore, any desired time lag can be adopted between the ignition of the first propulsive charge and that of any subsequent charge. By comparison with systems in which the propulsive charges have to be ignited in immediate succession to one another, in accordance with the existing prior art, this makes it possible for the second or further charges to be completely used for the additional acceleration of the projectile or payload to enable higher velocities and greater ranges to be obtained.

In the case of gas generators which are positioned separately from the ejection tubes and by which the propulsive gases are conveyed into the relevant ejection tubes through pipes it is desirable to position both the computer and the time switch element away from the gas generators and in the operating equipment. In this system the time switch element is connected to each gas generator primer capsule through an ignition cable.

The invention is further described with reference to embodiments shown by way of examples only in the drawings, wherein: Figures la-id show a double ended recoilfree expulsion system in four different operating states (a-d), Figure 2 shows a detail to an enlarged scale of the centre of the expulsion system shown in Figure 1a, Figure 3 shows a diagram of the individual components and the circuit of the time switch element, Figure 4 shows another embodiment of a double-ended recoil-free expulsion system, Figure 5 shows a propulsive charge system for a projectile, and Figure 6 shows a system of four expulsion tubes with two gas generators.

Referring to the drawings, Figure 1a shows a double-ended recoil-free expulsion system with a gas generator 1 having two propulsive charges 2 and 3, one within the other, and acting on payloads 5 through the piston 4. All the aforementioned parts are positioned in an expulsion tube 6.

Further details of the expulsion system will be explained later with reference to Figure 2. Figures 1b to 1d are intended to clarify the method of operation of an expulsion system of this kind when the two propulsive charges 2 and 3 are ignited in succession. In Figure 1b, for example, the middle expulsion charge 2 is ignited, whereupon the pistons 4 commence to operate moving the payloads 5 apart. In the state shown in Figure ic the outer propulsion charge 3 is ignited, thus increasing the acceleration of the payloads 5. In the state shown in Figure 1d not only the payloads 5 but also the pistons 4 have left the tube 6 and the surplus pressure of the propulsion charges 2 and 3 escapes.By varying the moment of ignition for the propulsive charge 3 by the aid of an ignition switch element to be described with reference to Figure 3, the expulsion speed of the payloads 5 can be steplessly controlled. On the other hand, it is also possible for the expulsion charge 3 to be ignited first, followed by the expulsion charge 2, or for only one of the two expulsion charges to be ignited.

Figure 2 is an enlarged illustration of the gas generator 1 with the two propulsion charges 2 and 3, of which the front sides are provided with perforations 7. The cylindrical propulsion charge 2 is ignited by a primer capsule 8 and the annular propulsion charge 3 by a primer capsule 9. The upper part of the propulsion charge 3 contains the ignition switch element 10 which is described later and via which the primer capsule 9 is ignited directly, the primer capsule 9 is ignited via a line 11.

The ignition switch element 10 is supplied with operating current and the control pulses through a line 13 from a computer 14 (not shown in the drawing). Both front plates of the propulsion charge 3 are closed by means of cover plates 12 dimensioned to resist the propulsive gases of a propulsion charge 2, although they can be opened by the pressure of the propulsive gases of the propulsion charge 3 acting towards the outside. The gas generator 1 is secured in the expulsion tube 6 by a screw 15. In this embodiment, with the gas generator 1 permanently built into the tube 6, the ignition switch element 10 can also be positioned outside the expulsion tube.

In Figure 3 the individual components of the ignition switch element 10 are situated inside a broken line. The feed line 13 from the computer 14 located externally leads to a signal decoder 16 and through two diodes 17 to the storage capacitors 18 associated with the two propulsion charges 2 and 3. The decoder 16 is connected to a timing unit 19 to which are connected two ignition switches 20 and 21 which are fed from the storage capacitors 18 and which can connect through to the primer capsules via lines 11 and 22. The method of operation of the ignition switch element 10 is as follows: the computer 14, programmed with the firing data, first of all effects through the line 13 the charging of the ignition capacitors 18.It then supplies the timing unit 19 through the decoder 16 with pulses in accordance with the ignition sequence times calculated to be the most advantageous, after which it supplies the ignition signal for the ignition of the first propulsion charge. The timing unit 19 stores the input time required for the ignition of the second propulsive charge and operates the switches 20 and 21 accordingly, thus effecting the ignition of the primer capsules 8 and 9.

Figure 4 shows a gas generator 1 which is not fixed in position in the expulsion tube 6 but is situated on one of the payloads 5, thus also serving as a piston. In this system the gas generator also only requires perforations 7 on one side. Here again, the computer 14 actuates the built-in ignition switch element 10 via the line 13, after the first propulsion charge has been ignited the line 13 is separated.

Figure 5 shows an application of the ignition apparatus to a weapon 25 in which a barrel 27 contains the two-part gas generator 28 similar to that shown in Figure 2 for firing a projectile 26, with an internal propulsion charge 29 and an external propulsion charge 30. To enable the ignition switch element 10 to be reused it is mounted separately from the barrel 27 of the weapon, as is the computer 14. As in the case of Figure 3, ignition lines 11 and 22 lead to the primer capsules 8 and 9.

A further embodiment of the invention shown in Figure 6 has an expulsion system in which two gas generators 32 and 33 are constructed as separate units and act on four expulsion tubes 38 to 41 through pipes 34 to 37. The expulsion tubes contain identical pistons 42 which act on payloads 43.

In this embodiment likewise any desired expulsion speeds for the payloads 43 can be obtained by selecting the moment for the ignition of the gas generators 32 and 33 by the computer 14 and the ignition switch element 10.

The invention is not confined to the examples shown as, by means of the computer 14 and the ignition switch element 10, the moments for the ignition of three and more propulsion charges can be determined in order to obtain still more differentiated or still higher expulsion speeds.

Claims (7)

1. Apparatus for the optional ignition of at least two propulsive charges or gas generators for the expulsion of projectiles or payloads from tubes, the apparatus having a computer to determine the ignition sequence of the propulsive charges or gas generators and an ignition switching element containing a timing unit connected to the computer with a storage capacitor for each propulsive charge and an ignition switch connected to the said capacitor and actuated by the timing unit, said switch serving to connect in circuit a primer capsule.

2. Apparatus in accordance with Claim 1, wherein each storage capacitor is preceded by a diode.

3. Apparatus in accordance with Claim 1 or 2, wherein a decoder is connected between the computer and the timing unit.

4. Apparatus in accordance with any one of Claims 1 to 3, wherein the ignition switching element is built into at least one of the propulsive charges or gas generators.

5. Apparatus in accordance with any one of Claims 1 to 3, wherein the ignition switching element is positioned outside the propulsive charges or gas generators.

6. Apparatus for ignition of at least two propulsive charges as herein described and exemplified with reference to the drawings.

7. Projectiles or payload expulsion apparatus as described herein and exemplified with reference to the drawings.