JP2934191B2 - Apparatus and method for generating impulse-like electromagnetic field - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an impulse electromagnetic field generator for intentionally generating an impulse electromagnetic field generated by electrostatic discharge.

[0002]

2. Description of the Related Art At a computer operation site, a catastrophic obstacle to a computer system (for example, a bank online) is caused by an electrostatic discharge generated by a contact (collision) between a charged metal object and another uncharged metal object. System stoppage, etc.) may occur. When such an indirect electrostatic discharge causes a failure, it is difficult to recognize it, unlike direct discharge from a charged human body to a device. For this reason, when investigating the cause of the failure, it is often the case that the investigation of the cause is prolonged or the cause is unknown.

[0003] In electrostatic discharge (ESD) between metal objects accompanying approach / collision, a charging potential (about 3 kV or less) is low enough to be invisible to human touch.
It has been recognized by an experimental study by the present inventor that an extremely strong impulse-like electromagnetic field is emitted into the space around a metal object ("Honda, Kawamura," Characteristics of ESD and its influence on computers "). (No. 2), “IEICE Technical Committee on Environmental Electromagnetics” and “Honda and Kawamura,“ ESD Features and Impact on Computers (Part 5) ”, IEICE Technical Committee on Environmental Electromagnetics”. Contrary to common knowledge, in such an electrostatic discharge, the lower the charged potential, the stronger the effect on electronic devices (M. Honda and T. Kawamura, "EMI C
haracteristics of ESD in A Small Air Gap ", EOS / ESD
Symp. Proc., EOS-6, pp. 124-130, 1984).

For example, when two non-grounded metal objects are fixed and both are brought close to each other by about several mm and a high voltage is applied to one of the metal objects, a discharge occurs. However, in such a state of the fixed discharge gap, the appearance of the generated transient electromagnetic field is a damped oscillation. It has been recognized from experiments and on-site failure records that such transient electromagnetic fields cause almost no damage to computer equipment. That is, in the latest computer equipment and communication equipment employing high-speed logic circuits, an impulse-like transient electromagnetic field often causes a failure rather than a continuous electromagnetic field.

[0005]

However, the current IEC standard (IEC 1000-4-2) defines an ESD test method on the assumption that a human body is charged, but it involves a collision near an electronic device. No consideration is given to ESD between metal objects. An ESD tester based on the current IEC standard has a capacitor (C = 150 pf) as a lumped constant corresponding to the capacitance (C) of the human body and a skin resistance (R) of a fingertip.
A fixed resistor (R = 330Ω) with a lumped constant suitable for the above is built in. This capacitor is charged once with a high potential of direct current (DC), and the charge is directly transferred to the surface of the electronic device through this resistor. It is structured to discharge. But,
Actually, due to the influence of the inductance existing in the discharge path, the discharge current waveform is often not sharp and oscillating.

[0006] Therefore, using the current ESD tester,
Even if the D tolerance test is performed, the failure cannot be reproduced because the electronic device such as a computer is different from the ESD between approaching / colliding metal objects actually encountered at the operation site. There are many problems, such as prolonged problems and taking measures other than electrostatic discharge. The cause of such problems is a scenario of equipment malfunction considered more than 20 years ago, that is, "malfunction of equipment is caused by charging of the human body and direct discharge from the fingertip to the surface of electronic equipment. In the related industry (related engineers). However, the actual cause of device malfunction is indirect ESD due to contact / collision between a metal object charged to a low potential and another non-grounded metal object. Such an event is liable to occur on a daily basis, for example, a collision between a charged steel pipe chair after a person has sat down and an uncharged steel pipe chair.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide an impulse electromagnetic field generator capable of easily generating an impulse electromagnetic field.

Another object of the present invention is to provide a resistance test method for testing the resistance of an electronic device to an impulse electromagnetic field generated by electrostatic discharge using such an impulse electromagnetic field generator. It is in.

[0009]

According to the present invention, there is provided an impulse-like electromagnetic field generating apparatus, comprising: a first conductor, a second conductor, and a third conductor held in a non-ground state;
Charging means for charging the first conductor to a predetermined potential; and moving the first conductor toward the second conductor at a predetermined speed .
The third conductor charged to the predetermined potential and the first conductor
The distance between the first and second conductors .
Moving means for colliding a conductor, and when the moving means collides with the first conductor and the second conductor, both the first and second conductors can move at least in the moving direction of the moving means Holding means for holding the second conductor in an unfixed state.

[0010] Particularly in the above-described structure, a third conductor which is charged at a predetermined potential, said first conductor and said third conductive
Changing the distance between the body said first conductor Ru is charged in unipolar with. In this manner, by performing charging by dynamic induction (details will be described later in the section of the embodiment of the invention),
The conductor can be charged uniformly at a higher density and with a single polarity, and a more pure impulse-shaped electromagnetic field can be obtained.

Preferably, the first and second conductors contact each other at at least two places during the collision to form a loop formed by the first and second conductors.

Preferably, the area formed by the loop at the time of collision between the first and second conductors is increased by the mobility of the first and second conductors at the time of collision caused by the holding means. Change.

[0013]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

<First Embodiment> [Principle of Generation of Impulsive Electromagnetic Field According to the Present Embodiment] Before describing the first embodiment, the principle of generation of an impulse electromagnetic field in the present embodiment will be described. FIG. 1 is a diagram illustrating the principle of generation of an impulse-like electromagnetic field according to the present embodiment. In the figure, reference numeral 1 denotes a metal object charged to a predetermined polarity, which is negatively charged in the figure. Note that the charging potential of the metal object 1 is about 3 kV, and is charged with a negative polarity in FIG. 1 (it goes without saying that it may be charged with a positive polarity). Reference numeral 2 denotes an uncharged metal object. When the metal object 1 is moved toward the metal object at a predetermined speed V and collides with the metal object 2, an impulse-shaped electromagnetic field is emitted in the movement axis direction due to the electrostatic discharge generated at this time. It is to be noted that, contrary to FIG. 1, even if the non-charged metal object is moved to collide with the charged metal object, an impulse-shaped electromagnetic field can be generated in the movement axis direction in the same manner. .

The metal object 2 is not grounded or fixed, and can be moved in the direction of movement of the metal object 1 at the time of collision with the metal object 1 so that a more reliable and strong impulse-shaped electromagnetic field can be generated. Can be generated. Further, the intensity of the impulse-shaped electromagnetic field changes depending on the charge amount and the collision speed of the charged metal object (the metal object 1 in this example).

The above events, that is, (1) an impulse-like electromagnetic field is generated by colliding a charged metal object and an uncharged metal object at a certain speed;
(2) It has been experimentally confirmed by the present inventors that the emission direction of the electromagnetic field is the direction of movement at the time of collision. An example of the experimental data is shown below.

First, an example of an experimental result showing the event (1) will be described with reference to FIG. A conductor charged at 3 kV has a speed v =
FIG. 2A shows the f-characteristics of an electromagnetic field generated when the conductor collides with an uncharged conductor at 30 cm / sec. FIG. 2 shows the f-characteristics of the electromagnetic field when two conductors are brought into contact at a speed v = 0 under the same charging conditions as in FIG.
(B) of FIG. In FIGS. 2A and 2B, the horizontal axis represents frequency, and the entire range is 0 MHz to 200 MHz.
0MHz, center at 1000MHz, 200MHz / DI
V. The vertical axis indicates the power level, and the reference level is 0 dBm, 10 dB / DIV. As is apparent from these f-characteristics, it is understood that when the conductor collides at a certain speed (30 cm / sec in this example), high energy can be obtained over a wide band including a high-frequency region. On the other hand, when the contact is made at a speed v = 0, energy can be obtained only in a narrow frequency range. This is achieved by colliding conductors
This indicates that an impulse-like transient electromagnetic field is generated.

As an example of an experiment showing the event (2), the intensity of an electric field generated by a monopole antenna arranged in the direction of motion and a monopole antenna arranged in a direction substantially perpendicular to the direction of motion is measured. Is mentioned.
In FIG. 1, reference numerals 3 and 4 denote 10 mm monopole antennas, respectively. In this experimental example, the monopole antenna 3 is arranged at a position 20 cm from the collision point of the metal objects 1 and 2 in the direction of movement of the metal object 1. The monopole antenna 4 is disposed at a position 15 cm from the collision point in a direction perpendicular to the axis of movement.

When the metal object 1 collides with the metal object 2 in the above state, the monopole antenna 3
While an impulse voltage of about 50 mV is obtained, the monopole antenna 4 can only obtain a voltage of about 250 mV in the form of an oscillating wave. From such experimental results, it is understood that a stronger electromagnetic field (impulsive electromagnetic field) is emitted in the direction of the movement axis.

[Example of Impulsive Electromagnetic Field Generating Apparatus] An example of an apparatus configuration for realizing the events described in the above operating principle will be described below.

FIG. 3 is a diagram for explaining the outline of the configuration of the impulse-like electromagnetic field generator according to the first embodiment. In the figure, reference numerals 10 and 11 denote metal objects, which are fixed to bearings 13 and 15 via supporting members 12 and 14 formed of an insulating material, respectively. The bearings 13 and 15 have a bearing structure inside, and slide the shaft 16 smoothly. Numerals 17 and 18 constitute a linear motor, and the mover 17 moves on the rail-shaped stator 18 under the control of the motor driver 19. The bearing 13 is connected to the mover 17, and when the mover 17 moves at the speed V1, the metal object 10 also moves at the speed V1.

Reference numeral 20 denotes a charging plate, which is charged to a predetermined potential by a power supply 21. In this example, the charging plate 20 is charged at a potential of 3 kV. Reference numeral 30 denotes an electronic device to be inspected, which is arranged on the movement direction axis of the metal object 10. Reference numeral 40 denotes a horn antenna for efficiently radiating the generated impulse-shaped electromagnetic field in a specific direction.

As described in the explanation of the principle, in order to generate an impulse-like electromagnetic field, it is necessary to charge one of the metal objects. In this example, the metal object 10 is charged. The charging method is as follows: (a) the metal object 10 is electrically connected to a power supply and charged by directly applying a potential;
(B) the metal object 10 is brought into contact with some insulator during the moving process, and the metal object 10 is charged by friction;
(C) bringing the metal object 10 closer to or away from the charged object at a certain speed to induce electric charge and charge the metal object 10;

It is well known that the metal object 10 is charged by the methods (a) and (b).
The method of charging the metal object 10 according to (b) will be apparent. However, the present inventor has found that the metal object is charged more uniformly, unipolarly without polarization, and uniformly by the method (c). That is, in FIG. 3, by moving the metal object 10 away from the charging plate 20 at the speed V1, the metal object 10 can be charged efficiently, uniformly and unipolarly. Therefore, in the present embodiment, the charging method according to the method (c) is employed.

In the impulse-shaped electromagnetic field generator according to the first embodiment, as shown in FIG.
By moving the metal object 10 at the speed V1 according to (7, 18), the metal object 10 can be charged to a single polarity. As in this example, a positively charged charging plate 20
When the metal object 10 is moved at a speed V1 in a direction away from the object, the entire metal object 10 is negatively and unipolarly charged. If the charging plate 20 is negatively charged, the reverse is true, and the entire metal object 10 is positively charged.

As described above, by moving the metal object 10 at the speed V1, the metal object 10 is inductively charged. Then, the charged metal object 10 moves at the speed V1.
As a result, the impulse-shaped electromagnetic field is generated as described in the above-described operation principle. . In addition, since the metal object 10 is uniformly charged to a single polarity by employing the charging by induction, a unipolar impulse can be generated. FIG. 4 is a diagram illustrating a state when the metal object 10 and the metal object 11 collide in the impulse-like electromagnetic field generation device according to the first embodiment.

Since the metal object 11 is movably supported by the bearing 15, when the metal object 10 collides with the metal object 11 at the speed V 1, both the metal objects 10 and 11 move in the moving direction along the axis 16. Then, the impulse-like electromagnetic field 31 is emitted in this movement direction, and the resistance of the electronic device 30 in the movement direction to the impulse-like electromagnetic field can be tested.

Each time the impulse-shaped electromagnetic field is emitted once, the metal objects 10 and 11 return to their initial positions (FIG. 2).
And the metal objects 10 and 11 need to be discharged. However, such a mechanism for returning to the initial state is obvious to those skilled in the art, and FIG.
4 can be additionally provided in the configuration shown in FIG.

As described above, according to the impulse-like electromagnetic field generator of the first embodiment, the impulse-like electromagnetic field can be efficiently emitted in a desired direction. Further, the intensity of the impulse-shaped electromagnetic field can be controlled by controlling the collision speed of the metal object 10. That is, the intensity of the impulse electromagnetic field can be controlled by controlling the speed of the linear motor.

Further, according to the configuration described above, it is possible to realize a compact impulse-shaped electromagnetic field generator. For example, the configuration as shown in FIG. 2 can be housed in a housing, and the horn antenna 40 can emit the impulse-shaped electromagnetic field 31. Since the impulse-like electromagnetic field generator can be miniaturized in this way, it can be brought to the actual operation site of an electronic device and subjected to an impulse-like electromagnetic field resistance test.

Further, since the impulse-like electromagnetic field generator of the present embodiment has a strong directivity, it is possible to perform a tolerance test on the electronic device 30 or the system in actual operation from various directions. And from the resistance test results,
Appropriate noise countermeasures can be taken for the electronic device 30 or the system, for example, by finding a part that is vulnerable to the impulse-like electromagnetic field and strengthening the shield at that part.

<Second Embodiment> Next, an impulse-like electromagnetic field generator according to a second embodiment based on the above-described operation principle will be described. FIG. 5 is a diagram illustrating a configuration of an impulse-like electromagnetic field generator according to the second embodiment. In FIG. 1, reference numeral 101 denotes a metal object having a U-shape. An elastic body 102 supports the metal object 101 and is formed of an insulating material. Reference numeral 103 denotes a metal object, also formed in a U-shape, and fixed to a shaft 104. The shaft 104 is formed of an insulating material and is connected to the gear 105. Reference numeral 107 denotes a motor, and the shaft 104
To rotate. For this reason, the rotation of the motor 107 causes the metal object 103 to rotate at the angular velocity V3 and collide with the metal object 101 (this state is indicated by a dashed line in FIG. 5).

Reference numeral 108 denotes a charging plate, and a power source 109
As a result, a predetermined potential is applied, and charged to a predetermined polarity. In this example, it is charged to a positive polarity. A motor driver 110 controls the driving speed of the motor 107 and the like. Thereby, the rotation speed of the metal object 103 is controlled. A horn antenna 111 efficiently radiates an impulse-shaped electromagnetic field 121 generated in the apparatus in a specific direction. Reference numeral 120 denotes an electronic device to be inspected.

In the above configuration, when the metal object 103 is set in the state shown by the solid line in FIG. 5 and the motor 107 is driven, the metal object rotates at the angular velocity V3. As a result, the metal object 103 is brought into a state indicated by a chain line,
It collides with the metal object 101. At this time, the metal object 103
It is desirable that the metal object 101 and the metal object 101 come into contact at two locations substantially simultaneously. When the metal objects 101 and 103 collide with each other at two positions, the metal objects
It has been found by the present inventors that a closed loop is formed by 1 and 103, and this formation of the closed loop can generate a stronger impulse-like electromagnetic field.

The operation of the impulse-like electromagnetic field generator according to the second embodiment will be described below with reference to FIGS.

First, as shown in FIG. 5, the metal object 103 is arranged close to the charging plate 108 in the initial state. The metal objects 101 and 103 in this state are shown by broken lines in FIG. In this state, the motor 107 is driven to rotate the metal object 103 at the angular velocity V3. Then, the metal object 103 separates from the charging plate 108 at a speed corresponding to the angular velocity V3, and as described in the first embodiment, the entire metal object 103 has a negative unipolarity and is uniform and high. Charged to density.

When the metal object 103 is further rotated, the metal object 103 collides with the metal object 101. That is, in FIG. 6, the metal object 103 indicated by a dashed line indicates the moment of collision with the metal object 101. As described above, the impulse-like electromagnetic field is generated by the collision between the metal objects. Further, since the metal object 101 is supported by the elastic body 102, as shown by a solid line in FIG.
01 moves in the collision direction. By setting the metal object 101 in a substantially non-fixed state in this way, the intensity of the impulse-like electromagnetic field generated at the time of collision increases.

As described above, in the second embodiment, when the metal objects 101 and 103 collide with each other, the two metal objects are substantially simultaneously brought into contact with each other at two places, thereby forming a closed loop. For this reason, the intensity of the generated impulse-shaped electromagnetic field could be further increased. This is thought to be because a strong magnetic flux is generated when a large current flows instantaneously in the closed loop formed by the metal objects 101 and 103, and this contributes to an improvement in the strength of the impulse electromagnetic field. Further, in the present embodiment, the metal object 101 is supported by the elastic body 102, and changes from the state of FIG. 9 to the state of FIG. 10 at the time of collision with the metal object 103. Therefore, the area of the closed loop formed by the metal objects 101 and 103 decreases at the time of collision. As a result, the magnetic flux density is increased, and a stronger impulse-like electromagnetic field can be generated.

As described above, in the impulse-shaped electromagnetic field generator of the second embodiment, when two metal objects collide, the two metal objects are brought into contact at two places to form a closed loop, and the closed loop is formed. , A stronger impulse-shaped electromagnetic field can be obtained. Note that the intensity of the generated impulse-shaped electromagnetic field is, as described in the first embodiment, the metal object 103.
Can be controlled by the collision speed (angular velocity V3). Therefore, by controlling the rotation speed of the motor 107 by the motor driver 110, the collision speed with the metal object 103 can be controlled, and the intensity of the generated impulse electromagnetic field can be controlled.

The direction of emission of the impulse-shaped electromagnetic field 121 is substantially the same as the direction of movement at the time of collision, so that directivity can be provided. Therefore, in FIG. 5, the antenna horn 111 and the electronic device 120 to be inspected are arranged so as to be arranged in a tangential direction of the rotation locus of the metal object 103 at the time of collision. As described above, in the second embodiment, the movement of the metal object is performed by the rotation operation. However, the impulse-shaped electromagnetic field generator in the second embodiment is also small and portable as in the first embodiment. The same advantages as those described in the first embodiment are provided. That is, the electronic device can be brought to the operation site of an actual electronic device and subjected to an impulse-like electromagnetic field resistance test. Further, since the impulse-like electromagnetic field generator of the second embodiment has a strong directivity similarly to the first embodiment, a tolerance test is performed on the electronic device 120 or system in operation from various directions. be able to. Then, an appropriate noise countermeasure can be taken for the electronic device 120 or the system, for example, by finding a portion that is weak to the impulse-shaped electromagnetic field from the test result and strengthening the shield of the portion.

It should be noted that the method of implementing the operation principle in the apparatus examples of the above embodiments is merely an example, and it is apparent that various modifications are possible. That is, various modifications made to the movement and collision mechanism of the metal object are all within the scope of the present invention.

[0042]

As described above, according to the present invention, it is possible to easily generate a very strong impulse-shaped electromagnetic field at an electronic device operation site.

Further, according to the present invention, there is provided a completely new resistance test method for examining the resistance of an electronic device to an impulse electromagnetic field.

[0044]

[Brief description of the drawings]

FIG. 1 is a diagram illustrating the principle of generation of an impulse-like electromagnetic field according to the present embodiment.

FIG. 2 is a diagram illustrating frequency characteristics of generated electromagnetic fields when a charged metal object collides with a non-charged metal object at a predetermined speed and when the metal object collides at substantially zero speed.

FIG. 3 is a diagram illustrating an outline of a configuration of an impulse-like electromagnetic field generation device according to the first embodiment.

FIG. 4 is a diagram illustrating a state when the metal object 10 and the metal object 11 collide in the impulse-like electromagnetic field generation device according to the first embodiment.

FIG. 5 is a diagram illustrating a configuration of an impulse-like electromagnetic field generator according to a second embodiment.

FIG. 6 is a diagram illustrating a state when a metal object and a metal object collide with each other in the impulse-like electromagnetic field generator according to the second embodiment;

[Explanation of symbols]

 10, 11, 101, 103 Metal object 12, 14 Support member 13, 15 Bearing 17 Mover 18 Stator 19, 110 Motor driver 20, 108 Charging plate 21, 109 Power supply 30, 120 Electronic device to be inspected 40, 111 Horn antenna

Claims (4)

(57) [Claims] 1. A charging means for charging a first conductor and a second conductor held in a non-grounded state, a third conductor to a predetermined potential, and charging the first conductor at a predetermined speed. 2 by moving toward the second conductor, the charged to the predetermined potential
Changing the distance between the third conductor and the first conductor;
To, a moving means for impinging first and second conductors, at the time of collision between the first conductor and the second conductor by said moving means, said first and second conductors are both at least impulsive electromagnetic field generating apparatus characterized by comprising holding means for holding the movable said second conductor in the moving direction by the moving means. 2. The method according to claim 1 , wherein the first conductor and the second conductor are connected in a non-ground state.
Holding , charging the third conductor to a predetermined potential, and moving the first conductor toward the second conductor at a predetermined speed.
By moving, the charged to the predetermined potential
Changing the distance between the third conductor and the first conductor,
This to obtain the impulse electromagnetic field to collide with the second conductor
And a method for generating an impulse-like electromagnetic field. 3. A first conductor and a second conductor held in a non-ground state.
2 conductor and one of the first and second conductors is monopolarly charged.
Charging means for moving the first conductor toward the second conductor at a predetermined speed;
Moving means for moving the first conductor and the second conductor by the moving means,
In the event of a collision, both the first and second conductors
At least in the moving direction by the moving means.
And a holding means for holding a second conductor, said first and second conductors, and characterized in that in contact with at least two positions at the time of the collision to form a loop by the first and second conductors Impulsive electromagnetic field emission
Raw equipment . Wherein the movability of the first and second conductors at the time of collision definitive in the holding means, the first and second
The impulse-shaped electromagnetic field generator according to claim 3, wherein the area formed by the loop is reduced at the time of collision of the conductor.