JPH0792214A - Electromagnetic wave generation equipment - Google Patents

Abstract

PURPOSE:To make it possible to improve generated electric field component of an electromagnetic wave with a small-sized noise resistance test equipment, by connecting a conical antenna in parallel to the opposite ends of a fuse- element through a tuning coil. CONSTITUTION:An insulating tube 21 is disposed on the upper part of a metal cylinder 1, a tuning coil 20 is wound spirally on the insulating tube 21 and the opposite ends of the coil are connected conductively to the metal cylinder 1 and a conical antenna 27 disposed above. The conical antenna 27 has a specific frequency characteristic according to the shape and dimensions thereof and can output an electromagnetic wave of a frequency of a maximum gain by regulating it so that the coil 20 and the conical antenna 27 may resonate. Thereby, a high electric field can be generated around it. Moreover, the generated electric field can be increased further by interposing a distributed contact line between a fuse-element 15 and the conical antenna 27.

Description

Detailed Description of the Invention

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic wave generator for converting explosive energy of explosives into a large current, generating a strong electromagnetic wave from the large current, and evaluating resistance to electromagnetic noise of electronic devices and the like.

2. Description of the Related Art FIGS. 6A and 6B are perspective views showing the operating principle of an electromagnetic wave generator using explosives. FIG. 6A shows a state before the operation, and FIG. 6A shows a metal cylinder 1 made of a good conductor such as copper, a winding 3, a current source 6 for supplying an initial current I _O to the metal cylinder 1 and the winding 3, and a short-circuit conductor 7 connected to the right end.
It is composed of and. Explosive 4 inside the metal cylinder 1
The detonator 5 is inserted into the left end so as to come into contact with the explosive 4. The winding 3 is wound in the axial direction of the metal cylinder 1 via the gap 2. When the explosive 4 is detonated by the ignition of the detonator 5 with the initial current I _O flowing, the explosion starts from the left end and propagates to the right.
FIG. 6 (B) shows a state in which the explosion of the explosive 4 is being propagated after the detonation, and the metal cylinder 1 is expanded outward by the detonation wave 8 and wound while crushing the void 2 from the detonator 5 side. The wire 3 and the metal cylinder 1 are pressure-bonded (hereinafter referred to as “explosion”). The blast surface 9 advances toward the short-circuit conductor 7 side as the detonation wave 8 progresses, and finally the metal cylinder 1 is entirely blast-bonded to the winding 3.
The principle of electromagnetic wave generation will be described below. Immediately before ignition of the detonator 5 in FIG.
_O is flown through the metal cylinder 1, the short-circuit conductor 7, and the winding 3, and a magnetic field (total magnetic flux amount is Φ) is formed in the cylindrical void 2. When the detonator 5 is ignited in that state, the state shown in FIG.
As shown in (B), the detonation wave 8 causes the explosive surface 9 to propagate to the short-circuit conductor 7 side at a velocity (about 9 km / s) approximately the same as the propagation velocity of the explosion. Since the explosive surface 9 progresses extremely rapidly in this way, even if the void 2 is crushed, the magnetic flux inside the void 2 cannot leak to the outside, and the value of the total magnetic flux amount Φ is preserved as it is. . That is, assuming that the inductance L _O is formed by the reciprocal circuit of the metal cylinder 1 and the winding 3 before the detonation, the total magnetic flux amount Φ formed by the initial current I _O is

[Number 1] can be expressed by _{Φ = L O · I O ···} (1). On the other hand, if the inductance created by the metal cylinder 1 and the winding 3 after the detonation is L and the output current flowing through the short-circuit conductor 7 at this time is I,

Φ = L · I (2) If equation (1) is equal to equation (2),

## EQU3 ## 1 / I _O = L _O / L (3) As the explosive surface 9 progresses to the short-circuit conductor 7 side,
Since the void 2 is crushed and the lengthwise distance of the remaining void 2 is reduced, the inductance L is reduced, the magnetic field in the void 2 is strengthened, and the output current I is increased from the equation (3).
This output current I flows through a closed loop formed by the metal cylinder 1, the short-circuit conductor 7, and the winding 3 through the explosive surface 9,
The ratio I / _IO to the output current I in the equation (3) corresponds to the current amplification factor. When this output current I flows through the winding 3, electromagnetic waves are generated in the surroundings. This device is a current amplifier that loads the short-circuit conductor 7, and is also called an explosive generator. A strong electric current can be generated by causing a current to rise rapidly to the megaampere order. FIG. 7 is a cross-sectional view showing a configuration example of a conventional electromagnetic wave generation device, in which stoppers 14 for closing the inside are arranged at both ends of the metal cylinder 1, and a detonator 5 is inserted in the lower stopper 14. Outside the metal cylinder 1, the winding 3 and the cylindrical support insulator 1 are provided.
3 and 3 are arranged. A spiral groove is provided on the inner wall of the support insulator 13, the winding 3 is housed in this groove, and a gap 2 is formed between the winding 3 and the metal cylinder 1. An insulating gap member 12 is interposed between the lower end of the winding wire 3 and the metal cylinder 1. On the other hand, between the upper end of the winding 3 and the metal cylinder 1, a short-circuit conductor 70 serving as both a load and a gap material is interposed. The winding 3 and the metal cylinder 1 are connected to the current source 6 at the lower ends. In FIG. 7, the detonator 5 detonates the explosive 4 while the initial current is applied to the winding 3, the short-circuit conductor 70 and the metal cylinder 1 by the current source 6. The explosion propagates upwards with time,
The current flowing through the winding 3 also increases, and a strong electromagnetic wave is generated in the surroundings. By placing an electronic device or the like at a position away from this device by a predetermined dimension, the noise resistance to the electric field E caused by the electromagnetic wave can be examined. The conductor width W of the winding wire 3 and the insulation gap D between the turns in FIG. 7 increase as they go upward. This is to reduce the inductance per unit length as going upward. This allows
As shown in the equation (3), the current amplification factor becomes large and a strong electromagnetic field can be obtained. FIG. 8 is a cross-sectional view of essential parts showing the configuration of a different conventional electromagnetic wave generator. The fusible body 15 is mounted from the upper end of the winding 3 toward the inner side in the radial direction, and
Is directly conductively connected to the outer diameter surface of. The fusible body 15 is scattered on the surfaces of the winding 3 and the metal cylinder 1 by soldering. Further, a pair of conical antennas 27 are attached to the winding 3 and the end of the metal cylinder 1, respectively. Other configurations are the same as those in FIG. 7. Further, FIG. 9 is a perspective view showing only one of the conical antennas 27 shown in FIG. The configuration of FIG. 8 is similar to that of FIG.
The same applicant has already filed a patent application that the generated electric field E will be orders of magnitude higher than in the above case. The generated electric field is increased because the fusible body 15 and the conical antenna 27 are provided. That is, the soluble body 15
Is temporarily liquefied by the output current I amplified by the explosion, and then becomes a plasma state. Generally, the resistance increase amount r per unit time when the metal is melted in a liquid state is very large. Therefore, the current flowing through the winding 3 increases, and when the fusible body 15 melts, the potential difference across the fusible body 15 suddenly increases rapidly. The generated electric field E increases in proportion to this potential difference. On the other hand, in the case of the device of FIG.
Since the short-circuit conductor 70 does not melt, the resistance increase r per unit time is zero, and the generated electric field E is determined only by the increase per unit time of the output current I due to the explosion. By interposing the fusible body 15, the generated electric field E can be extremely increased. Further, by providing the pair of conical antennas 27 at both ends of the fusible body 15, an electric field is also generated by the displacement current flowing between the pair of antennas. Since this electric field is added to the electric field due to the melting of the fusible body, the electric field component E of the electromagnetic wave is further increased.

However, the conventional device as described above has a problem that the electric field component of the generated electromagnetic wave is still low. That is, in the conventional device, the electric field EH generated at a point 50 cm away from the conical antenna in the radial direction is about 2 kV / m at most even when the output current I of 5000 A is caused to flow through the winding due to explosion. In order to evaluate the resistance to electromagnetic noise of electronic devices and the like, a generated electric field of several tens of kV / m is required, and conventionally, the output current I was increased to deal with the electric field. As a result, the entire apparatus becomes large and the test equipment is very expensive. An object of the present invention is to further increase the electric field component of electromagnetic waves.

In order to achieve the above object, according to the present invention, a metal cylinder having an explosive charged therein and a shaft while forming a cylindrical void portion outside the metal cylinder are provided. Winding wound in a direction, a support insulator that reinforces the winding from the outside, a detonator fitted to one end of the metal cylinder so as to contact the explosive, the metal cylinder and the winding. A current source connected in parallel between the ends of the wire on the detonator side, a fusible body connected in parallel between the ends of the metal cylinder and the winding on the anti-detonator side, and provided on the anti-detonator side of the winding It is composed of a pair of conical antennas that spreads outward in the radial direction in a conical shape.The explosive is detonated when the initial current is applied to the winding, and the current flowing in the winding is amplified to generate electromagnetic waves in the surroundings. In what makes a conical antenna a tuning coil To be deemed to have been connected in parallel with both ends of the fusible element. Further, to achieve the above object, according to the present invention, a metal cylinder having an explosive charged therein and a winding wound in the axial direction while forming a cylindrical void portion outside the metal cylinder. A wire, a support insulator for reinforcing the winding from the outside, a detonator which is inserted into one end of the metal cylinder so as to come into contact with the explosive, and an end of the metal cylinder and the winding on the detonator side. Current source connected in parallel between the parts, a fusible body connected in parallel between the metal cylinder and the end of the winding on the side opposite to the detonator, and a conical radially outward provided on the side of the winding opposite the detonator. It consists of a pair of conical antennas that spread like a coil, and it explodes an explosive in the state where an initial current is applied to the winding to amplify the current flowing in the winding to generate electromagnetic waves in the surroundings. Distributed constant filled with an insulator between the outer conductor A path is provided on the anti-detonator side of the winding, one end of the inner and outer conductors of the distributed constant line are connected to both ends of the fusible body, and the other end of the inner and outer conductors are connected in parallel to the conical antenna. In addition, in this configuration, the conical antenna is connected in parallel to the distributed constant line via the tuning coil. Further, in any one of the above configurations, it is assumed that the periphery of the fusible body is covered with explosive that contacts another detonator.

According to the structure of the present invention, since the conical antenna is connected in parallel to both ends of the fusible body through the tuning coil, if the tuning coil is adjusted so as to resonate with the frequency characteristic of the conical antenna, Since the conical antenna oscillates the electromagnetic wave having the frequency of the maximum gain, the generated electric field becomes high. Further, according to the configuration of the present invention, the distributed constant line is interposed between the conical antenna and the fusible body. The voltage generated at both ends of the fusible body enters the distributed constant line and is reflected at the end on the conical antenna side. Since the voltage amplitude is doubled by the reflection, the electromagnetic wave generated from the conical antenna becomes stronger and the generated electric field becomes higher. In such a configuration, the conical antenna is connected in parallel to the distributed constant line via the tuning coil. If the tuning coil is adjusted so as to resonate with the conical antenna, a voltage whose amplitude is doubled causes resonance due to reflection, and an electromagnetic wave having a higher electric field component is generated from the conical antenna. In any of the above configurations, the perimeter of the fusible body is covered with an explosive that contacts another detonator. If the explosive is ignited when the fusible material melts and is turned into plasma, the detoning force instantly compresses the plasma. At this time, the resistance increase amount r of the plasma per unit time is very large, so that the potential difference between both ends of the plasma instantly increases. As a result, the electric field generated from the conical antenna becomes higher.

EXAMPLES The present invention will be described below based on examples. FIG. 1 is a cross-sectional view of essential parts showing the configuration of an electromagnetic wave generator according to an embodiment of the present invention. An insulating cylinder 21 is arranged above the metal cylinder 1, and the tuning coil 20 is spirally wound around the insulating cylinder 21. Both ends of the tuning coil 20 are metal cylinders 1.
And conductively connected to the upper conical antenna 27.
Other configurations are the same as those of the conventional device shown in FIG. The same parts are designated by the same reference numerals, and detailed description thereof is omitted. The conical antenna 27 has specific frequency characteristics depending on its shape and size, and by adjusting the tuning coil 20 so as to resonate with the conical antenna 27, it is possible to output an electromagnetic wave having a maximum gain frequency. Thereby, a high electric field is generated in the surroundings. Figure 2
FIG. 4 is a sectional view of an essential part showing a configuration of an electromagnetic wave generator according to another embodiment of the present invention, in which an upper conical antenna 27 is attached to a metal cylinder 1 via a conductor cylinder 23, and a lower conical antenna 27 is tuned. It is conductively connected to the winding wire 3 via the coil 22. Others are the same as the configuration of FIG. The tuning coil 22 is spirally wound around the inner surface of the support insulator 13 and adjusted so as to resonate with the conical antenna 27. The configuration of FIG.
1. A series circuit of a conical antenna 27 and a tuning coil 22 is connected in parallel at both ends of, and the circuit is exactly the same as in FIG. Therefore, the strength of the output electromagnetic wave is also
1 and 2 are the same if the conical antenna 27 has the same shape and size. FIG. 3 is a cross-sectional view of essential parts showing the configuration of an electromagnetic wave generator according to a further different embodiment of the present invention. A distributed constant line 28 is interposed between the fusible body 15 and the conical antenna 27. In the distributed constant line 28, a cylindrical inner conductor 24 is arranged at the center, and a cylindrical outer conductor 25 is arranged on the outer periphery of the distributed constant line 28 via an insulator 26. The insulator 26 is made of water and has upper and lower insulating stoppers 29.
It is sealed by. The lower end of the inner conductor 24 is joined to the metal cylinder 1, and the upper end is joined to the upper conical antenna 27. On the other hand, the lower end of the outer conductor 25 is joined to the winding 3, and the upper end is joined to the lower conical antenna 27. Other configurations are the same as those in FIG. In FIG. 3, the distributed constant line 28 forms a distributed constant line such as a cable over the section of the axial length A, and the voltage generated at both ends of the fusible body 15 propagates upward on the distributed constant line 28. The upper end of the distributed constant line 28 has the conical antenna 2
Since it is terminated at 7, it is the same as when the termination is opened and no matching is obtained. Therefore, the transmitted voltage is
It is reflected by the conical antenna 27 at the end, and its voltage amplitude is doubled. Since the conical antenna oscillates the doubled voltage as an electromagnetic wave, a high electric field component is formed in the surrounding space. FIG. 4 is a cross-sectional view of essential parts showing the configuration of an electromagnetic wave generator according to a further different embodiment of the present invention. The insulating cylinder 21 is joined to the upper part of the internal conductor 24, and the insulating cylinder 2
The tuning coil 20 is wound around 1. Tuning coil 20
Has a lower end joined to the inner conductor 24 and an upper end joined to the upper conical antenna 27. Other configurations are shown in FIG.
Is the same as. In FIG. 4, the reflected wave of the distributed constant line 28 resonates due to the series circuit of the conical antenna 27 and the tuning coil 20, so that the generated electric field E becomes higher than in the case of the embodiment of FIG. FIG. 5 is a cross-sectional view of essential parts showing the configuration of an electromagnetic wave generator according to a further different embodiment of the present invention. The fusible body 15 is disposed in an insulative explosive container 30, and the explosive container 32 is loaded in the explosive container 30. Further, the detonator 31 is inserted so as to come into contact with the explosive 32. Other configurations are the same as those in FIG. In FIG. 5, when the fusible body 15 is melted by the output current I flowing from the winding 3 and turned into plasma, the detonator 31 is ignited to explode the explosive 32. Soluble body 15 made into plasma
Is instantly compressed radially inward by the detonation wave. At that time, the amount r of increase in resistance of plasma per unit time becomes very large. This increase in resistance r is several times larger than in the case of the melted melted body. As a result, a very high voltage component enters the distributed constant line 28, an electromagnetic wave several times stronger than in the case of the embodiment of FIG. 4 is generated from the conical antenna 27, and its electric field component E also becomes high. The configuration as shown in FIG. 5 in which the fusible body 15 is covered with the explosive 32 can also be applied to the embodiments of FIGS. 1 to 3, and the generated electric field E can be increased several times in each configuration.

The configurations of FIGS. 1 to 5 are referred to as Embodiments 1 to 5, respectively, and the result of obtaining the electric field E in the axial direction at a point 50 cm outward from the conical antenna 27 in the radial direction is shown in FIG. It is shown in Table 1 in comparison with FIG. 8).

[Table 1]In Table 1, in each of the examples, the output current I is 500
The fusible body 15 has a diameter of 0.16 mm and a length of 50.
5 mm copper wires are bundled into one, and this is 2 bundle winding 3
It was attached. The conical antenna 27 is shown in FIG.
D₁, D ₂120 mm, 240 mm, L is 12
0 mm, X is 30 degrees, and the distance between the conical antennas 27 is
The distance B (FIG. 1) was 100 mm. Further examples
Tuning coils 20 and 22 provided in 1, 2, 4 and 5
The conductance is 3 μH and the conical antenna 27 is
Electromagnetic waves mainly resonating with a frequency component of 30MHz
Oscillated. Furthermore, the components provided in Examples 3, 4 and 5
The cloth constant line 28 (FIG. 3) has an outer diameter Φ of the inner conductor 24.₁，
Inner diameter Φ of outer conductor 25₂60mm and 150m respectively
m, and the axial length A was 200 mm. Insulator 26
Since it is water (dielectric constant 80), this distributed constant line 28
The capacitance per unit of axial direction is 7,071p
F / m. In Table 1, the same as in Examples 1 and 2
The generated electric field E is
It is 1.5 times higher depending on the device. In addition, in the third embodiment
The electric field generated by the distributed constant line
E is 1.75 times higher. Furthermore, in Example 4.
In order to interpose both distributed constant line and tuning coil
Therefore, the superposition effect is recognized, and the generated electric field E is higher than that of the conventional device.
6 times higher. In addition, according to Example 5,
In addition to the structure of Example 4,
Electric field generated by the device that compresses with explosive
E is 3 times as much as that in the case of Example 4, and 18 times as much as that of the conventional apparatus.
Higher, so that an electric field of several tens of kV / m can be easily obtained
Became. This makes it possible to test the noise resistance of electronic equipment.
The equipment can be downsized.

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part showing the configuration of an electromagnetic wave generator according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of essential parts showing the configuration of an electromagnetic wave generator according to a different embodiment of the present invention.

FIG. 3 is a cross-sectional view of an essential part showing the configuration of an electromagnetic wave generator according to a further different embodiment of the present invention.

FIG. 4 is a cross-sectional view of an essential part showing the configuration of an electromagnetic wave generator according to a further different embodiment of the present invention.

FIG. 5 is a cross-sectional view of essential parts showing the configuration of an electromagnetic wave generator according to a further different embodiment of the present invention.

FIG. 6 is a perspective view showing the operating principle of an electromagnetic wave generator using an explosive, in which (A) is a state before the operation and (B) is a state during the operation.

FIG. 7 is a cross-sectional view showing a configuration example of a conventional electromagnetic wave generator.

FIG. 8 is a cross-sectional view of essential parts showing a configuration example of a different conventional electromagnetic wave generation device.

FIG. 9 is a perspective view showing only one of the conical antennas shown in FIG.

[Explanation of symbols]

1: metal cylinder, 2: void, 3: winding, 4,32: explosive, 13: support insulator, 39: insulator, 21: insulating cylinder,
14, 29: stopper, 15: fusible body, 23: conductor cylinder, 3
1: Detonator, 27: Conical antenna, 20, 22:
Tuning coil, 28: distributed constant line, 24: inner conductor, 2
5: outer conductor, 26: insulator, 30: explosive container

Claims (4)

[Claims] 1. A metal cylinder having an explosive charged therein, a winding wound in the axial direction while forming a cylindrical void portion on the outside of the metal cylinder, and a reinforcement of the winding from the outside. A supporting insulator, a detonator which is inserted into one end of the metal cylinder so as to be in contact with the explosive, and a current source which is connected in parallel between the metal cylinder and the end of the winding on the detonator side, It is composed of a fusible body connected in parallel between the ends of the metal cylinder and the winding on the side of the anti-detonator, and a pair of conical antennas provided on the side of the winding on the side of the anti-detonator and conically spreading outward in the radial direction. , In the case where an explosive is detonated in a state where an initial current is applied to the winding to amplify the current flowing in the winding to generate electromagnetic waves in the surroundings, a conical antenna is parallel to both ends of the fusible body via a tuning coil. Electromagnetic wave generation characterized by being connected Location. 2. A metal cylinder having an explosive charged therein, a winding wound in the axial direction while forming a cylindrical void portion on the outside of the metal cylinder, and a reinforcement of the winding from the outside. A supporting insulator, a detonator which is inserted into one end of the metal cylinder so as to be in contact with the explosive, and a current source which is connected in parallel between the metal cylinder and the end of the winding on the detonator side, It is composed of a fusible body connected in parallel between the ends of the metal cylinder and the winding on the side of the anti-detonator, and a pair of conical antennas provided on the side of the winding on the side of the anti-detonator and conically spreading outward in the radial direction. In the case where an explosive is ignited in a state where an initial current is applied to the winding to amplify the current flowing in the winding to generate electromagnetic waves in the surroundings, an insulator is filled between the inner conductor and the outer conductor. A distributed constant line is installed on the anti-detonator side of the winding and One end of the inner conductor and the outer conductor of the transmission lines are connected to both ends of each fusible element, electromagnetic wave generator, wherein the other end of the inner conductor and the outer conductor are connected in parallel to the conical antenna, respectively. 3. The electromagnetic wave generator according to claim 2, wherein the conical antenna is connected in parallel to the distributed constant line via a tuning coil. 4. The electromagnetic wave generator according to any one of claims 1 to 3, wherein the fusible body is surrounded by an explosive which contacts another detonator.