JPH062634B2 - Insensitive Initiator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to, for example, an insensitive type initiator that constitutes a part of an igniter of a solid rocket, more specifically, a bridge is energized to ignite an ignition charge and a flame thereof. The present invention relates to a desensitized type initiator in which the main charge of the igniter is ignited by igniting the charge.

(Prior Art) An insensitive initiator is required for, for example, a rocket igniter, and unless a predetermined current is applied to the bridge,
Even if an induced current is generated in the ignition system cable due to lightning or other external noise, it does not operate indefinitely.

FIG. 2 shows an example of a conventional initiator, where 1 is an initiator case, 2 and 2 are a pair of pins mounted in the case 1 via insulators 3 and 4, and 5 are pins 2 and 2.
A bridge such as a nichrome wire coil cross-linked at the front end (left side in the drawing) of the bridge, 6 is an igniting charge placed around the bridge, and 7 is a drug placed in the case 1 in front of the igniting charge. Cylinder, 8
Is a charge loaded in the medicine barrel, 9 is a sealing plate for sealing the front end of the medicine barrel 7, and the initiator having such a structure is provided with a male screw 1a formed at the front end of the initiator case 1. The charge 8 is made to face the main charge by being attached to the main charge case of the igniter. Therefore, when the connector of the ignition system cable is connected to the pins 2 and 2 and the current is energized in a timely manner, the bridge 5 generates heat to ignite the igniting charge 6, and the flame ignites the charge 8 to ignite the required amount. Releases the heat energy of. This causes the main charge to ignite and activate the igniter. In the conventional insensitive type initiator, the ignition sensitivity 6 is increased by adding an appropriately small amount of oxidizing agent to the main agent such as lead azide, which has a low thermal sensitivity. It was adjusted. Use a thermally insensitive explosive so that the ignition current does not ignite when the amount of heat generated by the electrode 5 is small due to an induced current that does not reach the specified value, or when the energization time is too short. There is.

(Problem) By the way, the insensitive igniter as described above generally has a small amount of heat generation per unit time or unit weight, so when an ignition charge is ignited using a small amount of igniter like an initiator. It is necessary to use a thermally sensitive explosive, generally an explosive, as the charge. However, since the explosive has a large explosive impact, there is a problem that the impact spreads to the main charge and damages it, or the weight of the igniter is increased because it is necessary to increase the strength of the igniter.

The present invention has been made in view of the above problems, and an object thereof is to obtain an insensitive type initiator which does not use a sharp explosive or the like as an igniter.

(Structure) In order to solve the above problems, the present invention has the following structure. As the insensitive type initiator, a pair of pins (2, 2) which are insulated from each other by the connector-side insulator (3) and the bridge-equipment-side insulator (14) and separated from each other in the initiator case (1), A bridge (5) bridged between the pins (2, 2), a metal powder having a high melting point and a body thermal conductivity and exhibiting normal temperature oxidation resistance and high temperature ignitability and a powdery oxidizer. The hybrid body is solidified with a binder to form a solid powder-containing powder powder, and the electric bridge (5)
The ignition charge (16) disposed around the battery and the charge (18) loaded on the entire end of the initiator case are accommodated, and the bridge (5) is electrically heated to generate the ignition charge (16). ) Is ignited, and the charge (18) is ignited by the flame.

Further, in this initiator, all the ends of the pins (2, 2) penetrate the insulator (14) on the electric bridge equipment side so that the front end faces of the pins (2, 2) and the front face of the plate material are flush with each other. It is desirable that the heat-resistant plate material (20) to be arranged is incorporated.

(Operation) When the initiator of the present invention configured as described above is used, the bridge (5) is energized at the time of ignition, the bridge (5) is red-heated, and the ignition charge (16) around the bridge is heated. When the temperature becomes high, the metal powder of the ignition charge (16) and the powdered oxidizer vaporize to cause an oxidation reaction with a high calorific value, and a high-temperature and high-pressure gas, that is, a flame is ejected, and the charge (18) is generated. Gives the temperature and pressure needed to ignite the.

The metal powder used here is a metal such as zirconium, tantalum, niobium, etc., which has normal temperature oxidation resistance, high temperature ignitability, high melting point and low thermal conductivity, and has oxidation resistance at room temperature. Since there is no risk of reaction during storage, it will be possible to stably store for a long time,
And because it has a high temperature ignitability, it easily ignites at high temperature and causes an oxidation reaction with a high calorific value, so it satisfies the characteristics as a component of a mixed explosive, and since it has a high melting point, it burns unless exposed to high temperature. It does not react, has insensitivity to temperature sensitivity, and has low thermal conductivity, so when heat is generated it locally raises the temperature rapidly and accelerates the oxidation reaction, satisfying the properties as an insensitive igniter. . Further, since the main component is a metal powder having a high melting point and a low thermal conductivity, the ignition sensitivity is easily adjusted and the desired desensitization to the ignition charge is facilitated by adjusting the particle size.

Accordingly, in the initiator using the ignition charge (16) of the present invention, when the bridge (5) is electrically heated during ignition, the ignition charge (16) is ignited at a predetermined combustion speed after reaching a predetermined temperature. However, the flame from the ignition charge (16) ignites the charge (18) without giving an excessive impact, and damages the target object such as the main charge of the flame ejected from the charge (18). Ignite without.

(Embodiment) FIG. 1 shows an embodiment of the present invention. Incidentally, the parts to which the same reference numerals are attached in FIG.

In the drawing, 20 is a heat-resistant plate material embedded in the insulator 14, for example, a ceramic plate material, and the pins 2 and 2 are provided.
Through the insulator 3, the insulator 14 and the plate member 20 so that the frontal surface thereof is exposed flush with the plate member 20, and the electric bridge 5 is welded to these frontal surfaces so as to be in close contact with the plate member 20 and crosslinked. There is. Reference numeral 16 is an ignition charge composed of the above-mentioned hybrid material, which is arranged around the electric bridge 5, and reference numeral 18 is an explosive having a small explosion impact, for example, explosives having a relatively low detonation speed such as boron-nitrite powder powder.

An example of the composition of the ignition charge 16 is shown.

Main agent: Zirconium particles Combustion heat 1959 Cal / g (from literature) Average particle size 2.5μ Mixing ratio 50% by weight Oxidizing agent: Potassium chlorate (KCLO ₄ ) Average particle size 10μ Mixing ratio 50% by weight Binder: Tetrafluoroethylene 3344555 This initiator The operation progress of was the same as that of the conventional one, and as a result of performing an operation test using the ignition charge having the above composition, a conducting current of the bridge was 1 ampere (power 1 watt),
It was confirmed that the ignition did not occur when the energization time was 1 minute, and thus the initiator could be surely deactivated by the induced current. Then, when the energizing current was set to the prescribed 5 amperes, the initiator could be operated instantaneously.

The plate material 20 made of ceramic or the like has a function of withstanding the high temperature flame of the ignition charge 16 and reflecting it forward while suppressing heat consumption, thereby improving the ignition performance to the charge 18. . Further, as described above, by closely contacting the bridge 5 with the plate member 20, it is possible to easily reduce the variation in the mutual positional relationship, and thereby, the variation in the amount of heat transfer from the bridge 5 to the plate member 20 is also reduced. Therefore, the reproducibility of the current range in which the initiator can be maintained inoperative is ensured.

(Effects) As described above, in the present invention, the ignition charge (16) is a composite of a powder of a metal having a high melting point and a body thermal conductivity, which exhibits oxidation resistance at room temperature and high temperature easy ignition, and a powdered oxidizer. Using solid explosive containing metal powder, which is hardened with a binder, electric bridge (5)
When the ignition charge (1) is heated by being energized, the ignition charge (16) ignites at a predetermined combustion speed, and the ignition charge (1)
The flame from 6) can ignite the charge (18) without giving an excessive impact, and the flame ejected from the charge (18) can ignite the target charge such as the main charge without damage. By doing so, it is possible to adjust the ignition sensitivity of the ignition charge (16) by arbitrarily selecting the particle size of the metal powder, and it is possible to prevent an excessive impact at the time of ignition from being generated. Can be realized.

Further, the particle size of the metal powder and the mixing ratio with the oxidizer can be appropriately selected, so that desired ignition resistance and heat generation amount can be adjusted.

Furthermore, since the metal powder has oxidation resistance at room temperature, it can be stably stored for a long period of time even if it is mixed with an oxidant, and can be stored for a long period of time, and the range of use of the initiator is expanded.

Moreover, since the calorific value at the time of burning the metal powder is large,
Even if the ignition characteristics of the ignition charge are desensitized, a sufficient amount of heat can be secured at the time of ignition, the ignition performance can be maintained, the degree of freedom in selecting the charge is increased, and the ignition impact is reduced due to the desensitization of the ignition charge. A charge can be loaded.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention, and FIG. 2 is a sectional view of a conventional initiator. DESCRIPTION OF SYMBOLS 1 ... Initiator 2 ... Pin 3 ... Connector side insulator 5 ... Electric bridge 14 ... Electric bridge equipment side insulator 6,16 ... Ignition charge 8,18 ... Launch charge 20 ... Plate material (heat resistant plate)

Claims (2)

[Claims] 1. An insulator case (1), an insulator (3) on a connector side, and an insulator (1) on a side equipped with a bridge.
4) a pair of pins (2, 2) insulated from each other and isolated from each other, a bridge (5) bridged between the respective pins (2, 2), normal temperature oxidation resistance and high temperature resistance. A mixture of a powder of an ignitable metal having a high melting point and a low thermal conductivity and a powdered oxidizer was solidified with a binder to form a solid powder containing metal powder, and the solid powder was placed around the electric bridge (5). The ignition charge (16) and the charge (18) loaded on the entire end of the initiator case are housed, and the bridge (5) is electrically heated to ignite the ignition charge (16). An insensitive initiator characterized by igniting the charge (18) with a flame. 2. An insulator (14) on the side of the electric bridge equipment
In addition, a heat-resistant plate material (20) for penetrating all the end portions of the pin (2, 2) and arranging the front end surface of the pin (2, 2) and the front surface of the plate material flush with each other is incorporated. The insensitive type initiator according to claim 1.