JP2007325457A - Magnetic-concentration-type explosive generator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve a current amplification factor by reducing impacts due to skin effects in a current amplification process while increasing the number of turns of a coil by inexpensively manufacturing the coils. <P>SOLUTION: A magnetic-concentration-type explosive generator 1A has a metal tube 6, which houses a detonator 7 for initiating an explosive 8 by imparting a starting signal, and the coil 2A arranged on the outer periphery of the metal tube 6. A current is made to flow in the coil 2A as the starting signal so as to execute amplification. The coil 2A is composed by using a rectangular wire that is formed by applying an insulating film onto a square conductor 3A whose cross-sectional shape is rectangular and in which a dimensional ratio between the long side and the short side of the cross section is more than three. The coil 2A is wound around the outer periphery of the metal tube 6 so that the long side of the cross section of the coil 2A becomes vertical to a coil axis aligned with a longitudinal direction of the magnetic-concentration-type explosive generator 1A via a prescribed interval. An insulating resin is molded between the turns of the coil 2A except a face where the coil conductor 3A and the metal tube 6 face to each other. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a magnetic concentration explosive generator that generates a large current pulse by sequentially short-circuiting energized coils with an explosive, and in particular, a device that converts a pulse current into a pulse voltage and a pulse voltage into an electromagnetic wave. The present invention relates to a magnetic concentrated explosive generator used in a portable electromagnetic wave generator that can generate a high output electromagnetic wave by combining with a conversion device and can be applied in various fields.

  The operation principle of a conventional magnetic concentrated explosive generator will be described with reference to FIGS. In FIG. 5, 1 is a magnetic concentrated explosive generator, 2 is a coil, 6 is a metal cylinder, 7 is a detonator, 8 is an explosive, and 10 is a wiring. A current flowing from the input side device (not shown) through the input side wiring 10 flows through the coil 2 to the output side device 10 via the output side wiring 10 and from the output side device. The current that has returned to the output-side wiring 10 flows from the metal cylinder 6 to the input-side wiring 10.

Here, if the current flowing through the coil 2 is I and the inductance of the coil 2 is L, a magnetic flux of L × I is generated in the coil 2. When the current flowing through the coil 2 reaches a peak, the detonator 7 is detonated and at the same time the explosive 8 is detonated and detonation is started.
As a result, as shown in FIG. 6, the metal tube 6 expands and the coil 2 is sequentially short-circuited, so that the inductance L of the coil 2 gradually decreases. On the other hand, since the magnetic flux L × I of the coil 2 is kept constant according to the magnetic flux conservation law, the current flowing through the coil 2 is amplified with time.

FIG. 7 shows how the current is amplified with time. As described above, the rate at which the current I is amplified is approximately proportional to the inductance L of the coil 2. Further, the inductance L of the coil 2 is approximately proportional to the number of turns of the coil 2. Therefore, it can be seen that the number of turns of the coil 2 should be increased in order to increase the current amplification factor represented by the output current / input current.
In addition, the coil 2 of the magnetic concentrated explosive generator 1 is manufactured by cutting a cylindrical metal, and then manufactured by applying an insulating coating or winding a circular conductor with an insulating coating. Has been.

FIG. 8 shows a cross-sectional configuration diagram of a conventional magnetic concentrated explosive generator in which a coil is manufactured by cutting the cylindrical metal described above. 8A is a sectional view in the longitudinal axis direction, and FIG. 8B is a sectional view taken along the line Z1-Z2 in FIG.
In FIG. 8, 1B is a magnetic concentration type explosive generator, 2B is a coil manufactured by applying a coating after cutting a metal tube, 3B is a conductor of the coil 2B, 4B is an insulation coating of the coil 2B, and 5 is an insulator. , 6 is a metal cylinder, 7 is a detonator, 8 is an explosive, and 9 is a flange.
Usually, since a metal cylinder with a thick cylinder cannot be obtained, a coil 2B is formed by cutting a thin cylinder. In order to pass a large current through the coil 2B, the conductor 3B has a rectangular cross section and has a predetermined current resistance, and the coil 2B is arranged such that the long side of the coil cross section is the length of the magnetic concentrated explosive generator 1B. The coil axis coincides with the direction so as to be parallel.

Next, FIG. 9 shows a cross-sectional configuration diagram of a conventional magnetic concentrated explosive generator in which a coil is manufactured by winding a circular conductor insulated wire having the above-described insulating film. 9A is a sectional view in the longitudinal axis direction, and FIG. 9B is a sectional view taken along the line Y1-Y2 in FIG.
In FIG. 9, 1C is a magnetic concentrated explosive generator, 2C is a coil manufactured using an insulated wire with a circular conductor provided with an insulating film, 3C is a conductor of coil 2C, 4C is an insulation coating of coil 2C, 5 is an insulator, 6 is a metal cylinder, 7 is a detonator, 8 is an explosive, and 9 is a flange. Since a large current flows through the coil 2C, the cross-sectional area of the conductor 3C needs to be the same as that of the conductor 3B of the flat rectangular coil 2B of FIG.

As this type of conventional apparatus, there is one described in Patent Document 1, for example.
JP 2003-298352 A

  However, the conventional magnetic concentrated explosive generator has the following problems. Magnetic concentrated explosive generator coils are manufactured by cutting a cylindrical metal material to produce a conductor, then performing an insulation film treatment on the conductor, and then molding an insulating resin between the coils. Become. Even if a thick metal cylinder can be obtained, it takes a lot of time and money for cutting and insulation treatment, and the manufacturing cost becomes high.

In addition, since a large current flows through the coil, the coil cross-sectional area increases, and particularly the axial dimension of the coil increases, so the number of turns of the coil cannot be increased. Therefore, the current represented by the output current / input current The gain cannot be increased.
In addition, when a coil is manufactured using a circular conductor wire having an insulating coating, it can be manufactured at a low cost. However, as described above, the coil cross-sectional area needs to be increased. Therefore, the number of turns of the coil cannot be increased, and the amplification factor of the current expressed by the output current / input current cannot be increased.

Furthermore, in the conventional coil configuration, in the process of amplifying the current, the frequency of the current increases as the rise of the current increases, so that the current becomes a high-frequency current, and the current is applied only to the surface of the conductor by the action of the skin effect. The resistance value of the conductor becomes high, and current amplification is hindered.
The present invention has been made in view of such a problem, and can produce a coil at a low cost. In addition, the number of turns of the coil can be increased and the influence of the skin effect in the current amplification process can be achieved. An object of the present invention is to provide a magnetic concentration type explosive generator capable of increasing the current amplification factor by reducing the current.

  In order to achieve the above object, a magnetic concentration type explosive generator according to claim 1 of the present invention includes a metal cylinder containing a detonator for initiating an explosive by giving an activation signal, and a coil disposed on the outer periphery of the metal cylinder. In the magnetic concentrated explosive generator that amplifies the coil by passing current through the coil, the coil is a rectangular conductor having a rectangular cross section and a dimensional ratio of the long side / short side of 3 or more. Is used as a coil conductor, and the coil conductor is formed on the metal cylinder so that the long side is perpendicular to the coil axis that coincides with the longitudinal direction of the magnetic concentrated explosive generator body. The coil conductor is wound around the outer periphery at a predetermined interval, and the coil conductor is formed by insulating the coil conductor with an insulating material except for the surface facing the metal tube.

  According to this configuration, since the short sides of the coil cross section are arranged in the coil axis direction, the number of turns of the coil is increased, and the current amplification factor expressed by the output current / input current can be increased. it can. Moreover, since the side of the coil cross section perpendicular to the coil axis can be made long (long side), the circumference of the coil conductor can be made long, thereby reducing the coil resistance value against high-frequency current. And the influence of the skin effect in the current amplification process can be reduced. Furthermore, since a rectangular electric wire having an insulating coating applied to the coil in advance is used, the coil can be manufactured at low cost.

  As described above, according to the magnetic concentrated explosive generator of the present invention, the coil can be manufactured at low cost, the number of turns of the coil can be increased, and the skin effect in the current amplification process can be increased. By reducing the influence, there is an effect that the current amplification factor can be increased.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, parts corresponding to each other in all the drawings in this specification are denoted by the same reference numerals, and description of the overlapping parts will be omitted as appropriate.
(Embodiment)
FIG. 1 shows a cross-sectional configuration of a magnetic concentrated explosive generator according to an embodiment of the present invention, where (a) is a cross-sectional view in the longitudinal axis direction, and (b) is a cross-sectional view along X1-X2 in (a). .
In FIG. 1, 1A is a magnetic concentrated explosive generator, 2A is a coil, 3A is a coil conductor, 4A is a coil insulation coating, 5 is an insulator, 6 is a metal tube, 7 is a detonator, 8 is an explosive, 9 is It is a flange.

  The magnetic enriched explosive generator 1A of the present embodiment is different from the conventional magnetic enriched explosive generator in that the coil 2A has a rectangular cross-sectional shape and a dimensional ratio of the long side / short side of 3 or more. The rectangular conductor 3A is a rectangular electric wire coated with an insulating film, and the coil 2A has a long side in the cross section of the coil 2A perpendicular to the coil axis that coincides with the longitudinal direction of the magnetic concentrated explosive generator 1A. Is wound around the outer periphery of the metal cylinder 6 at a predetermined interval, and the insulating film is formed by molding an insulating resin between the coils 2A except for the surface where the coil conductor 3A faces the metal cylinder 6.

According to the magnetic concentrated explosive generator 1A having such a configuration, since the short side of the cross section of the coil 2A is arranged in the coil axis direction, the number of turns of the coil 2A increases accordingly, and the output current / input current Can be increased.
Moreover, since the rectangular electric wire by which the insulating film was previously given to the coil 2A is used, the coil 2A can be manufactured at low cost.
Furthermore, since the side perpendicular to the coil axis of the cross section of the coil 2A can be made long (long side), the circumference of the coil conductor 3A can be made long, thereby reducing the coil resistance value against high-frequency current. As described in detail below, the influence of the skin effect in the current amplification process can be reduced.

The effect of reducing the effect of the skin effect will be described in detail.
FIG. 2A shows an initial current distribution flowing through the cross sections of the coil 2A of the present embodiment shown in FIG. 1 and the conventional coils 2B and 2C shown in FIGS. The initial current is close to direct current and is not affected by the skin effect because the frequency is low, and the current flows through the entire inner surface of the coil cross section as expressed in black.
FIG. 2B shows a current distribution in the coil cross section in the current amplification process in each of the coils 2A, 2B, and 2C. The frequency of the current increases with current amplification and reaches a maximum of 50 kHz. The depth at which the current flows is calculated from the skin effect calculation formula (1):
δ = {2 / (ωμσ)} ^0.5 (1)
It is represented by

Here, ω is an angular frequency of 2πf (f is a frequency), μ is the permeability of the coil conductor (copper), and σ is the conductivity of the coil conductor (copper).
Substituting f = 50 × 10 ³ , μ = 4π × 10 ⁻⁷ , and σ = 0.5 × 10 ⁸ into the above equation (1), the depth δ = 0.3 mm. That is, the current flows between the coil surface and a position deeply lowered by 0.3 mm from the coil surface. Since the cross-sectional area through which the current flows is δ × the circumference of the coil, the longer the circumference of the coil, the smaller the resistance value of the coil.

FIG. 3 shows an example of the circumference of the coil. A section 2A is a coil according to the present embodiment, 2B is a coil manufactured by cutting a conventional cylindrical conductor, and 2C is a coil using a conventional circular conductor insulated wire. Moreover, the coil shape in each coil 2A-2C in order from the top, a coil cross-sectional area, and the circumference ratio of a coil cross section are shown.
When the cross-sectional area of the initial conductor is the same, the circumference of the coil 2A is 20% or more longer and the coil resistance is 20% or more smaller than that of the conventional coils 2B and 2C. It becomes less susceptible to the skin effect, and therefore the rate at which current amplification is inhibited is smaller.

  The reason why the long / short side of the coil cross section is defined as 3 or more is that the number of turns of the coil 2A according to the present embodiment is increased by about 20% from the number of turns of the conventional coils 2B and 2C. It must be compensated that the resistance value also increases by about 20%. That is, it is for reducing the increase in resistance value due to the skin effect in the current amplification process of the coil 2A by 20% or more.

(Example)
Next, an example of the magnetic concentrated explosive generator 1A of the present embodiment will be described.
In FIG. 1, the conductor 3A of the coil 2A is a rectangular wire having a length of 12 mm and a width of 2 mm, a polyester film of 0.03 mm as the insulating film 4A, a coil of 75 turns with an inner diameter of 15 mm and a pitch of 4 mm. The inductance of the coil 2A was 100 μH.
Here, a method of forming the coil 2A will be described. First, a flat electric wire is wound in contact with a slippery cylindrical resin such as Teflon (registered trademark) resin while adjusting the tension so that the long side of the coil cross section is perpendicular to the axial direction of the resin. Thereafter, a resin having good electrical insulation such as an epoxy resin is poured, and when the resin is hardened, the cylinder of Teflon (registered trademark) resin is removed.
When such a magnetic concentrated explosive generator 1A was operated, 50 times was obtained as a current amplification factor represented by output current / input current.

Next, for comparison with the magnetic concentrated explosive generator 1A of the present embodiment, the conventional magnetic concentrated explosive generator shown in FIGS. 8 and 9 was manufactured as follows.
In the conventional magnetically concentrated explosive generator shown in FIG. 8, the conductor 3B of the coil 2B is 6 mm long and 4 mm wide, an inner diameter of 15 mm, a coil pitch of 6 mm, and a 50-turn coil. The inductance of the coil 2B was 70 μH. When this magnetic concentrated explosive generator was operated, a current amplification factor of 30 was obtained.

In the conventional magnetically concentrated explosive generator shown in FIG. 9, the conductor 3C of the coil 2C is a circular conductor having a diameter of 5.5 mm, and a 40-turn coil is formed with an inner diameter of 15 mm and a coil pitch of 7.5 mm. The inductance of the coil 2C was 50 μH. When this magnetic concentration type explosive generator was operated, a current amplification factor of 25 times was obtained.
The temporal characteristics of these current amplification factors are shown in FIG. In FIG. 4, the same reference numerals as those of the coils 2A, 2B, and 2C are assigned to the respective curves.
As described above, according to the magnetic concentrated explosive generator 1A of the present invention, the coil 2A can be manufactured at a low cost, and the number of turns of the coil 2A is increased, and the current amplification process is performed. Therefore, the current amplification factor can be increased.

The cross-sectional structure of the magnetic concentration type explosive generator which concerns on embodiment of this invention is shown, (a) is sectional drawing of a longitudinal-axis direction, (b) is X1-X2 sectional drawing of (a). It is explanatory drawing of the skin effect in an electric current amplification process. It is a figure which shows the example of calculation of the circumference of the coil in the magnetic concentration type explosive generator of this Embodiment. It is a characteristic view of the current amplification factor of the magnetic enrichment type explosive generator according to the present embodiment and the conventional magnetic enrichment type explosive generator. It is a figure which shows the structure of the conventional magnetic concentration type explosive generator. It is a principle figure which shows the action | operation of the conventional magnetic concentration type explosive generator. It is a characteristic figure of the current gain of the conventional magnetic concentration type explosive generator. The cross-sectional structure of the conventional magnetic concentration type explosive generator is shown, (a) is sectional drawing of a longitudinal-axis direction, (b) is Z1-Z2 sectional drawing of (a). The cross-sectional structure of the other conventional magnetic concentration type explosive generator is shown, (a) is sectional drawing of a longitudinal-axis direction, (b) is Y1-Y2 sectional drawing of (a).

Explanation of symbols

1A, 1B, 1C Magnetic concentrated explosive generator 2A, 2B, 2C Coil 3A, 3B, 3C Coil conductor 4A, 4B, 4C Coil insulation coating 5 Insulator 6 Metal cylinder 7 Detonator 8 Explosive 9 Flange 10 Wiring

Claims (1)

In a magnetic concentrated explosive generator that has a metal tube containing a detonator for initiating an explosive by giving an activation signal, and a coil disposed on the outer periphery of the metal tube, and amplifies the current by flowing current through the coil,
The coil has a rectangular cross section and uses a rectangular electric wire with an insulating film applied to a rectangular conductor having a dimensional ratio of 3 or more as a long side / short side as a coil conductor. Wrapped around the outer periphery of the metal cylinder at a predetermined interval so as to be perpendicular to the coil axis that coincides with the longitudinal direction of the magnetic concentrated explosive generator body, except for the surface where the coil conductor faces the metal cylinder, A magnetic enriched explosive generator characterized in that the coil conductors are insulated with an insulating material.

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