KR200207558Y1 - The electromagnetic wave absorptive devices for computer monitor - Google Patents

Abstract

The present invention relates to a harmful electromagnetic wave absorbing device of a computer that can prevent the computer operator from being exposed to harmful electromagnetic waves generated by a computer monitor when operating the computer, and a powdered absorber or sintered to absorb harmful electromagnetic waves in a plastic case. It is characterized in that the absorber ceramics and the electromagnetic wave absorber blocking the bottom surface to the case by incorporating the bottom plate of the plastic case by embedding a foam-iron iron plate as an electromagnetic wave absorber above and below the absorber, respectively.

Description

Electromagnetic wave absorptive devices for computer monitor

The present invention relates to a harmful electromagnetic wave absorbing device from a computer monitor to prevent the operator from being exposed to harmful electromagnetic waves generated and emitted from the computer monitor when operating the computer. Computers that accurately and quickly process modern information and bulk tasks in modern life are equipped with components to achieve a certain purpose in a small space. It is well known that branches emit electromagnetic waves.

However, even though the electromagnetic waves do not generate sound, light, and heat, they are difficult to detect by the five senses of humans, and they know that electromagnetic waves adversely affect the human body. The computer is being manipulated.

Of course, if you have a constant working time and a sufficient rest time when working with a computer, it is possible to recover within the body and it will not affect the human body, but the reality is that almost all workers watch the computer monitor for a long time. With the advent of the Internet, more and more teenagers are watching the monitors, which is likely to cause widespread damage caused by electromagnetic waves.

In particular, scientists are advised to take sufficient time to rest after watching the monitor for a certain period of time and to avoid working for more than 20 hours a week for pregnant women.

However, in reality, it is very difficult to keep this, and it is essential that an electromagnetic wave shielding device having an appropriate efficiency is essential, and research for this is very active. However, until now, electromagnetic wave blocking devices are often designed to enter the interior of electrical and electronic devices, which not only complicates the device but also increases the cost. Therefore, the development of a simple but effective device that can block electromagnetic waves is inevitably required.

The present invention is to solve the problems as described above, the computer monitor 100 to the electromagnetic wave absorbing device 10 of the simple form of the harmful electromagnetic wave generated and emitted from the computer monitor 100 when performing the operation by operating the computer The purpose is to protect the operator of the computer from harmful electromagnetic waves by blocking the electromagnetic waves generated and emitted from the computer monitor 100 by attaching the adhesive member to the four front corners of the case.

As a means for achieving the above object, the present invention is to put the powder-absorbing body 30 or the sintered ceramic absorber (30a) to absorb harmful electromagnetic waves in the plastic case 40, and the foam-coated steel sheet as an electromagnetic wave absorber above and below the absorber Each of the built-in (20) is characterized in that the electromagnetic wave absorption blocking device fixed by welding a high frequency welding the bottom plate of the plastic case.

In addition, the electromagnetic wave absorption blocking device 10 manufactured in the above manner is attached to four corners of the front surface of the computer monitor 100 by using an adhesive member so as to block the electromagnetic wave emitted during the use of the computer.

Other objects and advantages of the present invention will be described below and will be appreciated by the embodiments of the present invention. Further objects and advantages of the present invention will be realized by means and combinations particularly pointed out in the appended claims.

1 is a state diagram installed in the monitor the electromagnetic wave absorber of the present invention

2 is a block diagram of a plastic case containing the electromagnetic wave absorber of the present invention

3 is a perspective view of the plastic case of the present invention

4 is a block diagram of a ceramic electromagnetic wave absorber of the present invention

5 is a configuration diagram of the foam Royer electromagnetic wave absorber of the present invention

6 is a cross-sectional view of a state in which a powder absorber is filled in a plastic case;

7 is a cross-sectional view of a powder absorber and a foam steel sheet filled in a plastic case;

8 is a cross-sectional view of a state in which a sintered ceramic absorbent is mounted in a plastic case and a foam steel sheet is filled;

[Explanation of symbols on the main parts of the drawings]

10 Electromagnetic wave absorber 20 Formaloy steel plate (nickel molybdenum alloy steel plate)

30 powdery electromagnetic wave absorber 30a sintered ceramics electromagnetic wave absorber

100 computer monitor 40 plastic case

Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a computer monitor 100

2 is a configuration of a plastic case containing the electromagnetic wave absorbers 30 or 30a and 20 of the present invention

3 is a perspective view of a plastic case 40 to incorporate the electromagnetic wave absorbers 30 or 30a and 20 of the present invention.

4 is a block diagram of the sintered ceramics electromagnetic wave absorber (30a) of the present invention

5 is a configuration diagram of the electromagnetic wave absorber 20 of the foam steel sheet of the present invention

Figure 6 is a cross-sectional view of the electromagnetic wave absorbing device filled with the powdery absorber 30 in the plastic case in the present invention

FIG. 7 is a cross-sectional view of the electromagnetic wave absorbing device 10 in a state in which the powdery absorber 30 and the foam steel sheet 20 are filled in the plastic case 40 according to the present invention.

8 is a cross-sectional view of the electromagnetic wave absorbing device 10 in a state where the sintered ceramic absorber 30a and the foam steel sheet 20 are filled in the plastic case 40 according to the present invention.

The electromagnetic wave absorbing device 10 of the present invention basically has a shape as shown in FIG. 2, and the present invention has a foam which is a nickel molybdenum alloy steel sheet and any one selected from a powdery electromagnetic wave absorber 30 and a sintered ceramic electromagnetic wave absorber 30a. The Roy steel sheet 20 is disposed therein to manufacture an electromagnetic wave absorbing device 10 that absorbs and blocks harmful electromagnetic waves.

The external shape of the electromagnetic wave absorbing device 10 is made of a circular or oval as shown in Figure 3 and is configured to be easily attached to the four corners of the case of the computer monitor 100 as an adhesive subsidiary and nickel molybdenum alloy steel sheet ( 20, the sintered ceramics electromagnetic wave absorber 30a positioned between the parts has a shape similar to the main surface of the plastic case 40 of FIG. 3, and the sintered ceramics electromagnetic wave absorber 30a has a plastic case 40 as shown in FIG. 4. ) And a size of a suitable size, the perspective view of the electromagnetic wave absorber foam (nickel molybdenum alloy steel sheet) 20 was made in the form as shown in FIG.

The powdered electromagnetic wave absorber 30 embedded in the plastic case 40 is 1.8 to 2.0 wt% of yttrium oxide (y ₂ O ₃ ), 0.04 to 0.09 wt% of potassium oxide (K ₂ O), and titanium oxide (TiO _2). ) 0.02 to 0.09 weight%, sodium oxide (Na ₂ O) 0.29 to 0.38 weight%, manganese dioxide (MnO ₂ ) 14.0 to 15.0 weight%, zinc oxide (ZnO) 15.0 to 16.5 weight%, iron oxide (Fe ₂ O ₃ ) 65.0 ~ 75.0 wt%, calcium oxide (CaO) 0.05-0.09 wt%, silicon oxide (SiO ₂ ) 0.60-0.85 wt%, nickel oxide (NiO) 0.01-0.03 wt%, and chromium oxide (Cr ₂ O ₃ ) 0.01- Manganese zinc-based electromagnetic wave absorber blended 0.05% by weight according to physical properties, and the powdered electromagnetic wave absorber had 5000 ± 20% at 25% of initial permeability, 400mT at 25 ° C, 260mT at 100 ° C, Residual flux density 150 mT at 25 ° C, Coercivity 12A / m at 25 ° C, relative loss factor 5 × 10 ^-5 at 25 ° C, Curie temperature (curie temperature) is more than 12 ℃, resistivity 25 ℃, 0.2 초과 m, Density has a characteristic of 4.85 × kg / ㎡ at 25 ℃.

After uniformly kneading the powdered manganese zinc-based electromagnetic wave absorber, the well-kneaded powder was wet pulverized and spray dried in a furnace at 400 ° C. to 600 ° C. to form granular powder having a particle size of 1 to 3 μm, and then to a granular shape. The powder is press-molded at a pressure of 700 to 1300 kg / cm 2 to produce a desired molded body.

When the compact is completed, the compact is loaded into a closed kiln, and nitrogen (N ₂ ) is added for 30 minutes, and when the furnace temperature reaches 1300 ° C. to 1400 ° C. over 9 hours, a temperature of 1300 ° C. to 1400 ° C. is reached. The molded product deposited in the kiln is fired by holding for 3 to 3 hours. After the constant temperature is maintained for a certain time, nitrogen (N ₂ ) is added to the kiln again, and the mixture is cooled slowly for 8 to 9 hours until the temperature in the furnace reaches 200 ° C. in a nitrogen atmosphere. The reason for the slow cooling of the sintered compact is that since the sintered sintered compact is ceramics, if the temperature is rapidly lowered, cracks or breakages occur on the surface of the sintered compact due to the difference in the expansion coefficient of each material constituting the sintered compact.

More preferably, when the sintered body is cooled, nitrogen is introduced into the furnace while the sintered body is in the sintering step, and the sintered body loaded in the sintering furnace is slowly cooled to remove the sintered body loaded in the sintering furnace when the temperature in the furnace reaches 200 ° C. or lower. It is good to cool in. The sintered ceramics, which have undergone the sintering firing process and the cooling process, are manufactured with a harmful electromagnetic wave absorber ceramics to be obtained as a conductive magnetic material having a spin structure in which the positive and negative directions of atoms of the sintered object are crossed with each other.

In addition, the use of nickel (Ni)-molybdenum (Mo) steel sheet as an electromagnetic wave absorber is more effective to block the electromagnetic waves generated and generated by the computer monitor when the computer is operating, so that people who operate the computer are harmful to electromagnetic waves. The composition ratio of nickel (Ni)-molybdenum (Mo) is 50 to 54% by weight of nickel (Ni), 10 to 12% by weight of molybdenum (Mo), 30 to 32% by weight of iron (Fe) %, 0.5-1 weight% manganese (Mn), and 0.5-1 weight% of other minerals.

6 is a cross-sectional view illustrating a state in which the powdery absorbent body 30 is filled into the plastic case 40 of the present invention.

7 is filled with a powdery absorbent body 30 in the plastic case 40 of the present invention, and inserted into a foamy steel sheet absorber 20 having a thickness of 0.25 mm above and below the powdery absorbent body 30 or the powdery absorbent body 30. The top and bottom of the 0.50mm thick foam steel sheet absorber 20 is inserted in a cross-sectional view

FIG. 8 is a cross-sectional view showing a state in which a foamed steel sheet having a thickness of 0.35 mm is inserted into and above and below the sintered ceramic electromagnetic wave absorber 30a in the plastic case 40 of the present invention.

As described above, the present invention inserts a nickel molybdenum (Ni-Mo) alloy steel sheet absorber up and down into the powdery absorber 30 and the sintered ceramic electromagnetic wave absorber 30a to form the electromagnetic wave absorber 10. An example is shown.

And finally, Figure 1 shows an embodiment of a state in which the electromagnetic wave absorbing device 10 of the present invention is attached to the computer monitor 100.

As shown, since the electromagnetic wave absorbing device 10 of the present invention is manufactured in a small size, the electromagnetic wave emitted from the computer monitor 100 can be easily and easily absorbed and blocked by attaching to the four corners of the front surface of the monitor housing (case) 100. Will provide a beneficial effect.

Hereinafter, the effect of the electromagnetic wave absorbing device 10 of the present invention through the test embodiment of the present invention.

[Test Example 1]

The material of the electromagnetic wave absorber 30a to be filled in the plastic case 40 is a manganese zinc-based material described in detail in the section [Design of the Invention], and the negative (+) and negative (-) atoms of the atoms constituting the material. It is a ferrimagnetic ceramic having a structure in which directions cross each other, that is, a spin structure.

In this test example 1, the material constant of the ceramic composition was measured, and the change in the radiation pattern of the flexible antenna by the small electromagnetic wave absorber manufactured by the composition was investigated through a simulation using FDTD.

1. Sample Specification

① Shape: annular cylinder (cylindrical)

② Length: 7.4mm

③ Inner Radius: 4.0mm

④ Outside Radius: 6.0mm

2. Measuring method

Coaxial line reflection / transmission method

(Refer to Hewleh-Packard Product Note Number 8510-3) and measure S ₂₁ Transmission Loss in the frequency band of 0.5 to 2.0 에서 at 23 ± 1 ℃ and humidity below 55% RH. Calculate the electromagnetic wave absorption rate from.

In addition, the complex vision ratio and the boxer specific permeability at 835MHz are measured, and the attenuation constant and the propagation constant are obtained using this.

3. Measuring device

① HP 8501 B Network Analyzer

② HP 8515 A S-Parameter Test Set (45MHz-26.5㎓)

③ HP 83620 A Synthesized Sweeper (10MHz-20MHz)

④ MmC 2653 H Readless Airline (length 30mm)

4. Radiation Pattern Simulation

◇ Simulation condition

1) Numerical Analysis Techniques:

2) Coordinate System: FDTD (Finitd Difference Time Domain) Method

3) FDTD unit cell size: 5mm × 5mm × 5mm

4) Observation frequency: 835MHz

5) Antenna Specification: Dipole, Length 165mm, Located on Z-axis

6) Boundary conditions: 300mm × 300mm × 295mm

Moore's second order boundary condition is applied to x = ± 150, y = ± 150, z = ± 147

7) Small Absorber: Size-100mm × 10mm × 5mm

Space-10∠X∠20, -5∠Y∠5, -2.5∠Z∠2.5

The results are shown in Table 1 below.

〈Table 1〉

On the other hand, the reflection power ratio, transmission power ratio, and absorption power ratio for the manganese zinc-based ferrimagnetic ceramic composition itself having the spin structure, and the reflection coefficient, transmission coefficient, and reflection power ratio measured for 835 MHz by fabricating the composition with a flat plate having a thickness of 1.00 mm , The transmission power ratio and the absorption power ratio are as described in Table 2 below.

<Table 2>

From the results shown in the table above, the attenuation constant (241 NP / m) and the propagation constant (208 rad / m) calculated using the complex and complex permeability ratios are similar to each other. It can be seen that the conductivity is large.

In addition, a ferrimagnetic electromagnetic wave absorber having a manganese zinc-based spin structure, as seen from the results of Table 1, in which the absorption power ratio is high and the transmission power ratio is low for a 835 MHz flat plate perpendicularly incident on a 1.00 mm thick plate prepared using the composition. It can be seen that the product has excellent performance as an electromagnetic wave absorber.

The result of simulation by FDTD method is that the reduction of radio wave is about 3.2dB when the distance is 27.5mm from the antenna and about 1.3dB when the distance is about 32.5mm.

(Test Example 2)

As a result of measuring the attenuation of the electromagnetic field emitted by the computer monitor 100 operating in three times with the absorption device 10 having the electromagnetic wave absorber 30a of the first embodiment, Table 3 and same.

The magnetic field measuring instrument used in this study is an electronic field measuring instrument 'PSMA01' manufactured by Pulse Co., Ltd. of Korea.

Measuring range --- 30-2㎑

Sensitivity --- 0.1-199.9mG

Magnetic axis --- shorten

Tolerance --- 5% of Readibg (-10 ℃ ~ -70 ℃)

Power --- 9V DC Single Power

Current consumption-10 mA

The measurement results are as follows.

〈Table 3〉

(Test Example 3)

The present invention is a computer monitor in which the manganese zinc-based powdered electromagnetic wave absorber 30 described in detail in the configuration of the present invention in the plastic case 40 is filled with an electromagnetic wave absorber device 10 which is operated for three times. Measurement results of the attenuation of the electromagnetic field emitted by 100) are shown in Table 4 below.

〈Table 4〉

(Test Example 4)

Into the plastic case 40 of the present invention, the manganese zinc-based powdered electromagnetic wave absorber 30 described in detail in the present [Constitution of the present invention] is filled, and then 0.35 mm thick foamy is formed above and below the powdered electromagnetic wave absorber 30. The attenuation of the electromagnetic field emitted by the computer monitor 100 operating with the electromagnetic wave absorbing device 10 formed by inserting two sheets of steel sheet electromagnetic wave absorbers 20 is shown in Table 5 below.

〈Table 5〉

(Test Example 5)

After filling the manganese zinc-based powdered electromagnetic wave absorber 30 described in detail in the present invention [Constitution of the present invention] in the plastic case 40 of the present invention, a 0.50mm-thick foamy foam is formed above and below the powdered electromagnetic wave absorber 30. The attenuation of the electromagnetic field emitted by the computer monitor 100 operating with the electromagnetic wave absorbing device 10 formed by inserting two sheets of steel sheet electromagnetic wave absorbers 20 is shown in Table 6 below.

〈Table 6〉

(Test Example 6)

In the plastic case 40 of the present invention, the manganese zinc-based sintered ceramics electromagnetic wave absorber 30a described in detail in the present [Configuration of the Invention] is filled, and then a 0.35 mm thick foam Roy is placed on and under the electromagnetic wave absorber 30a. The attenuation of the electromagnetic field emitted from the computer monitor 100 operating with the electromagnetic wave absorbing device 10 formed by inserting two sheets of steel sheet electromagnetic wave absorbers 20 is shown in Table 7 below.

〈Table 7〉

The present invention is not limited to the above-described test embodiments, and various modifications and variations are made by those skilled in the art to which the present invention pertains without departing from the spirit of the present invention and the equivalent scope of the claims set forth below. Of course this is possible.

As described above, by operating the computer of the present invention, the harmful electromagnetic waves generated and emitted from the computer monitor 100 are blocked by the externally attached circuit breaker in a simple form to be emitted from the computer monitor 100. It provides the effect of protecting the human body from harmful electromagnetic waves.

Claims (3)

The powdery absorbent body 30 or the sintered ceramic absorbent body 30a is filled into the plastic case 40 of the present invention, and the powdery absorbent body 30 or the sintered ceramic absorbent body 30a filled in the plastic case 40 is placed above and below. Electromagnetic wave absorbing device for computer monitor 100, characterized by inserting two foam molybdenum steel sheet electromagnetic wave absorber 20, which is nickel molybdenum alloy steel According to claim 1, the material of the powdery absorbent body 30 or the sintered ceramic absorbent body 30a contained in the plastic case 40 of the present invention is 1.8 to 2.0 wt% of yttrium oxide (y ₂ O ₃ ) and potassium oxide (K _2). O) 0.04 to 0.09 weight%, titanium oxide (TiO ₂ ) 0.02 to 0.09 weight%, sodium oxide (Na ₂ O) 0.29 to 0.38 weight%, manganese dioxide (MnO ₂ ) 14.0 to 15.0 weight%, zinc oxide (ZnO) 15.0 ~ 16.5 wt%, iron oxide (Fe ₂ O ₃ ) 65.0-75.0 wt%, calcium oxide (CaO) 0.05-0.09 wt%, silicon oxide (SiO ₂ ) 0.60-0.85 wt%, nickel oxide (NiO) 0.01-0.03 wt% %, And a manganese zinc-based ferrimagnetic material composed of 0.01 to 0.05% by weight of chromium oxide (Cr ₂ O ₃ ) electromagnetic wave absorbing device 50 to 54% by weight of nickel nickel (Ni) for nickel molybdenum alloy steel sheet inserted into and below the powdery absorbent body 30 or the sintered ceramic absorbent body 30a incorporated in the plastic case 40 of the present invention. , 10-12 wt% molybdenum (Mo), 30-32 wt% iron (Fe), 0.5-1 wt% manganese (Mn) and 0.5-1 wt% of other minerals