JP3050242U - Mobile phone case - Google Patents

Abstract

(57) [Problem] To provide a mobile phone case using an electromagnetic wave shielding material and capable of avoiding an adverse effect on a human body without deteriorating a transmission / reception function of the mobile phone. SOLUTION: In a mobile phone case using an electromagnetic wave shielding material formed by knitting conductive fibers and using a base cloth such as a synthetic leather to which the electromagnetic wave shielding material is bonded, an electromagnetic wave generated from an antenna is generated by a user. An antenna cap having an opening so as not to radiate in a direction is connected to the case and used.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to a mobile phone case using an electromagnetic wave shielding material that blocks electromagnetic waves such as radio waves and microwaves (ultra-high frequency waves) generated from the mobile phone.

[0002]

[Prior art]

 The mobile phone emits a high-frequency electromagnetic wave of, for example, 800 MHz to 1.5 GHz. Recently, medical problems such as malfunction of medical equipment and breakdown of cardiac pacemakers due to this electromagnetic wave have become social problems.

In addition, there is a risk that a computer may malfunction and cause a serious accident due to use of the mobile phone in a car, an airplane or the like controlled by the computer. Furthermore, most home appliances around us are sources of electromagnetic waves, but research has begun on the danger that high-frequency electromagnetic waves may harm human cells or the immune system. Since mobile phones are used close to the brain, their effects are greatest and risky.

[0004]

[Problems to be solved by the invention]

 The present invention relates to a mobile phone case that uses an antenna cap with an opening so as to be connected to the above case so that transmission and reception with the outside can be performed but electromagnetic waves generated from the antenna do not radiate in the direction of a user (in particular, a head). For the purpose of providing.

[0005]

[Means for Solving the Problems]

 The mobile phone case of the present invention uses an electromagnetic wave shielding material knitted with conductive fiber, and is generated from an antenna in a mobile phone case using a base fabric such as synthetic leather to which the electromagnetic wave shielding material is bonded. An antenna cap having an opening so as not to radiate electromagnetic waves in the direction of the user is connected to the case and used.

The antenna cap has a cylindrical shape in which the upper portion is smaller in diameter than the lower portion, and a conductive hook in contact with the antenna, which assists in the emission or reception of radio waves, is provided on the upper opening edge of the antenna cap toward the outside of the telephone. It is characterized by being provided in.

[0007]

[Embodiment of the invention]

 FIG. 6 is an external view of a mobile phone case using an electromagnetic wave shielding material of the present invention, and FIG. 7 is a partially enlarged view thereof. The mobile phone case of the present embodiment is made of synthetic leather in which an electromagnetic wave shielding net 2 in which conductive fibers are knitted with a coarseness of 1.5 mm or less is bonded to the base cloth, or this synthetic leather is lined. Leather fabric is used.

FIG. 1 is an enlarged view of the electromagnetic wave shielding net used in the mobile phone of the present invention. The electromagnetic wave shielding net 2 is made of conductive fibers such as metal fibers (silver, copper, nickel, etc.), carbon fibers, etc., having a micron order and serving as an electromagnetic wave shielding material, and synthetic fibers such as polyester as a base material. The conductive fibers obtained by knitting are knitted by a general knitting machine such as a tricot knitting machine. It has a roughness of 1.5 mm or less, which is known.

Further, a semi-finished product of the electromagnetic wave shielding net 2 knitted as described above is dyed by spraying, for example, a black acrylic dye containing a solvent. The base polyester fiber is melted by the dye solvent, and then solidified to fix the stitch of the electromagnetic wave shielding net 2. The purpose of dyeing the electromagnetic wave shielding net 2 in black, for example, is to glue it to a transparent soft sheet material, as described later, to make the characters on the operation panel easy to see when used on the operation panel of a mobile phone case. For this reason, the color to be dyed may be a color other than black, and an acrylic dye may be sprayed only for the purpose of solidifying the stitch without dyeing.

The electromagnetic wave shielding net 2 does not require a special knitting machine, uses a small amount of fiber, and has a large area for shielding electromagnetic waves like large home appliances such as a washing machine and a dryer. Even in this case, the cost can be kept low. Further, the electromagnetic wave blocking net 2 has a structure in which the vertical and horizontal fibers of the stitch restrain each other's movement, so that the stitch roughness is maintained at 1.5 mm or less, which has an electromagnetic wave blocking effect, and a high-frequency electromagnetic wave of 200 MHz or more is generated. Cut off nearly 100%.

[0011] Furthermore, due to the conduction between the fibers entangled at the intersection of the stitches, the reflection and absorption of the electromagnetic wave increases, and the effect of blocking the electromagnetic wave increases. In addition, by twisting, the conductive fiber becomes coiled, the surface area increases, the amount of reflection and absorption of electromagnetic waves increases, and the effect of blocking electromagnetic waves is high. In this example, a metal fiber, a carbon fiber, or the like is described as a fiber in which a synthetic fiber such as polyester is twisted. However, it is also possible to twist a metal fiber, a carbon fiber, or the like alone. .

FIG. 2 is an exploded structural view of an example of the electromagnetic wave shielding material. The electromagnetic wave shielding material of the present embodiment is obtained by bonding the electromagnetic wave shielding net 2 as described above to the adhesive surface of the adhesive sheet 31. Before use, the adhesive surface is covered with a release paper 33 coated with silicone. Have been done.

The electromagnetic wave shielding material of the present embodiment is obtained by forming the electromagnetic wave shielding net 2 in a step of winding an adhesive sheet 31 coated with an adhesive on one surface of a support together with a release paper 33 into a roll in a normal adhesive sheet manufacturing process. It can be manufactured by supplying it and wrapping it between the release paper 33.

The electromagnetic wave shielding material of this embodiment is suitable for lining because it can be easily adhered by simply attaching it to metal, synthetic resin, or the like. Specifically, it is suitable for lining mobile phones.

FIG. 3 is a perspective view of another example of the electromagnetic wave shielding material. The electromagnetic wave shielding material of the present example is a sheet material 41 provided with decorative elements such as wallpaper and curtain, and the above-described electromagnetic wave shielding net 2 bonded to the back surface. The electromagnetic wave shielding effect can be obtained without impairing the decorativeness of the sheet material 41 including the target element.

FIG. 4 is an exploded structural view of still another example of the electromagnetic wave shielding material. In the figure, 1 and 3 are soft sheet materials made of transparent and flexible polyvinyl chloride (PVC), 2 is the above-mentioned electromagnetic wave shielding net, and the stitch roughness is 1.5 mm or less, and it is transparent. Roughness that maintains lightness (a). The electromagnetic wave shielding material of the present invention is obtained by laminating the above-mentioned soft sheet materials 1 and 3 on both surfaces of the electromagnetic wave shielding net 2 by laminating (b).

The electromagnetic wave shielding material (transparent laminate sheet) of this embodiment is transparent, flexible, and elastic. In this embodiment, the soft sheet materials 1 and 3 are laminated on both sides of the electromagnetic wave shielding net 2 by laminating, but the soft sheet material 1 or 3 becomes the surface of the electromagnetic wave shielding material. The structure may be such that only one side of the net 2 is bonded by lamination.

FIG. 5 is an exploded structural view of still another example of the electromagnetic wave shielding material. In the drawing, reference numeral 11 denotes a synthetic leather base cloth made of a tricot fabric having a small shrinkage, that is, a non-stretchable fabric. The above-mentioned electromagnetic wave shielding net 2 is bonded to the base cloth 11 (a) and (b).

Next, the surface of the base cloth 11 on which the electromagnetic wave shielding nets 2 are bonded together is coated with polyurethane resin to form a synthetic leather surface layer 13 (c). ). The coating method is to wet-coat the polyurethane resin and then dry-coat it. The electromagnetic wave shielding material of this example does not lose its shape even when sewed in a three-dimensional shape such as a storage case of a mobile phone, and has a high-grade feeling.

The electromagnetic wave shielding net and the electromagnetic wave shielding material used in the present invention as described above are: The electromagnetic wave blocking net 2 having a mesh size of 5 mm or less has a function of reflecting or absorbing the electromagnetic wave and converting it into heat energy, and blocks 97 to 98% of a microwave of 200 MHz or more. However, with a roughness of 1.5 mm or more, the shielding effect decreases in proportion to the size of the eyes.

The electromagnetic wave shielding material is knitted with a general knitting machine such as a tricot knitting machine because the conductive fibers are knitted in a mesh shape with a stitch roughness of 1.5 mm or less. The amount of fiber used is small, the cost is low even if the area that blocks electromagnetic waves is large, and the stitch length and width restrain the movement of each other so that the coarseness of the stitch is kept constant. In addition, the conductive amount of the fibers entangled at the intersection of the stitches increases the amount of electromagnetic wave reflection and absorption, and the electromagnetic wave shielding net has a high electromagnetic wave shielding effect, so it is suitable for use as the case material of the present invention. As an example, the feature of the present invention lies in the structure of the case of the mobile phone. For example, a material for OA apron using cloth coated with nickel on polyester, cloth made of metal fiber, or the like may be used.

Hereinafter, specific embodiments of the mobile phone case of the present invention will be described. FIG. 6 is an external view when the mobile phone case of the present invention is mounted on the mobile phone. As shown in FIG. 7, the antenna A has a cylindrical shape with an upper portion smaller in diameter than the lower portion and is made of the same synthetic leather as described above or a leather base 22 lined with this synthetic leather. It is covered with a detachable antenna cap 21. The upper opening of the antenna cap 21 is opened in a predetermined direction (a direction not facing the user when using the mobile phone: in this example, the right side of the mobile phone) to a position 1 cm or more below the upper end of the antenna cap 21. And the inner wall surface is covered with an insulator. The electromagnetic wave generated from the antenna A is guided by the upper opening in a predetermined direction that does not affect the user.

The upper opening of the antenna cap 21 is opened to the position of the upper end of the antenna A stored in the mobile phone main body or to a position where the upper end is slightly exposed from the lower edge of the opening. . The antenna cap 21 has such a diameter as to substantially contact the antenna A at the position of the lower edge of the opening.

A hook-shaped one end of a ground E made of a conductive material is hooked at a position on the upper opening edge of the antenna cap 21 so as to contact the upper end of the antenna A. The earth E assists the induction of electromagnetic waves by the upper opening and the emission or capture of communication radio waves by the antenna A.

Since the antenna cap 21 has a cylindrical shape in which the diameter of the portion covering the upper end of the antenna A is smaller than the diameter of the opening at the lower end, the upper part of the electromagnetic wave from the antenna A blocked by the side wall of the antenna cap 21 To prevent the spread of The antenna cap 21 can be easily removed when, for example, the antenna is to be extended and used.

An elastic sheet coated with, for example, the above-described synthetic leather is used on the back surface of the case that should cover the back surface of the mobile phone to reduce the impact applied to the mobile phone. If the elastic sheet and the leather material 22 are quilted to prevent stretching, the elastic sheet and the leather material 22 are prevented from being stretched, so that the electromagnetic wave shielding effect is maintained. The antenna cap 21 is used in connection with the mobile phone case body at a high frequency. The two need only be connected at a high frequency and need not necessarily be fixed.

Further, in the mobile phone case of the present embodiment, a transparent laminate sheet 24 having an electromagnetic wave shielding effect having a structure as shown in FIG. 4 is used for operation parts such as keys and switches of the mobile phone. The positions and functions of keys and switches can be visually recognized from the outside of the case, and the keys and switches can be operated from the outside. A similar transparent laminate sheet 24 may be used for the portion covering the display. However, when the display is a liquid crystal, the generation of electromagnetic waves is small. It can be sufficiently blocked by the electromagnetic wave blocking material.

The outer periphery of the case is trimmed with a synthetic leather trimming tape 23. A plurality of holes are provided at respective positions S 1 and M corresponding to a speaker and a microphone of the mobile phone, and the diameter of each hole is 1.5 mm or less.

As described above, in the mobile phone case using the electromagnetic wave shielding material of the present invention, the electromagnetic wave shielding net 2 having a coarseness of 1.5 mm or less reflects or absorbs the electromagnetic waves, and the thermal energy is reduced. It has a function of converting microwaves of 200 MHz or more from 97 to 98%. However, with a roughness of 1.5 mm or more, the shielding effect decreases in proportion to the eye roughness.

Therefore, the above-mentioned mobile phone case can easily operate the operation panel surface of keys, switches, and the like of the electronic devices housed therein from the outside, and it is hard to get dirt. There is no collapse of the case sewn in three dimensions.

In the present embodiment, a configuration is described in which the electromagnetic wave shielding net 2 is sandwiched between the entirety of the soft sheet materials 1 and 3 or bonded to the whole of the base cloth 11, the adhesive or adhesive sheet 31, and the sheet material 41. , May be sandwiched or bonded together. Further, a configuration in which the electromagnetic wave blocking nets 2 are scattered may be used.

The results of measuring the local, radio wave and power densities of a mobile phone equipped with a mobile phone case using the electromagnetic wave shielding material of the present invention and a mobile phone not equipped with the same are shown below (ambient temperature 20 ° C., Humidity 53%).

The mobile phone to be measured stands on a table 1.1 m above the ground with the antenna housed, and the operation mode is set to dial transmission, and it takes a long time for the operation to stabilize. And then measure. The measurement points (height) are measured at two places: the center of the key panel (the above-mentioned operation panel) and the center of the antenna. The measurement direction is the front (the operation panel of keys, switches, etc.) at each measurement point. Side), the right side (the side with the antenna), the left side, and the back side, and the measurement distance is 0 cm in the case of magnetic field measurement. The distance closest to the sensor is close contact, that is, the measurement distance is 0 cm.), 2.5 cm, 5 cm, 10 cm, 30 cm, and 5 cm, 10 cm, 30 cm for electric field / power density measurement.

For the measurement, an MA841 type (model: MA841D mover K) was used as a mobile phone, CLOSE-FIELD PROBE (HP11940A: manufactured by Hewlett Packard) was used as a sensor for measuring magnetic field intensity and electric field intensity, and a spectral analyzer was used as a measuring device for magnetic field intensity. (R3261B: manufactured by Advantest) and a BROADBAND EXPOSURE METER (manufactured by HO LADAY INDUSTRIES) was used as an electric field strength measuring instrument. The sensor and the measuring instrument are connected by a coaxial cable having a length of 10 m. The settings of the spectrum analyzer are 1 MHz for the span, 10 kHz for the resolution bandwidth, 10 kHz for the video bandwidth, and the peak value for the detection function. The measurement frequency is 946.4 MHz, the cable loss is 2.2 dB, and the antenna factor is 27.1 dB {(μA / m) / (μV)}.

[0035]

[Table 1]

[0036]

[Table 2]

[0037]

[Table 3]

[0038]

[Table 4]

[0039]

[Table 5]

[0040]

[Table 6]

[0041]

[Table 7]

[0042]

[Table 8]

From the above magnetic field measurement results, taking data of a measurement distance of 2.5 cm in the front direction (a-1) as an example, the magnetic flux density without the cover is calculated as follows. . Magnetic field strength H = 57.2 + 2.2 + 27.1 = 86.5 [dBμA / m] = 10 ^{(86.5 / 20)} × 10 ⁻⁶ [A / m] = 0.0211 [A / m] Magnetic flux density B = μ ₀ H = 4π × 10 ^-7 × 0.0211 [Wb / m ² ] = 0.266 × 10 ^-7 [Wb / m ² ] = 0.266 [mG] (μ ₀ : magnetic permeability)

Similarly, a magnetic flux density of 0.2 cm at a measurement distance of 2.5 cm with the cover is present. 0691 is obtained. At this time, the attenuation rate is obtained as follows. Attenuation rate = (0.266-0.0691) /0.266 x 100 = 74.0 [%]

At this time, the measured height at the center of the key panel is a distance of 0 cm in the right, left, and back directions other than the front direction and a distance of 10 cm in the right direction, and the measured height of the antenna center is the rear. The magnetic field is increasing at a distance of 0 cm in the direction. Therefore, it is clear that the mobile phone case using the electromagnetic wave shielding material of the present invention reflects the electromagnetic waves in directions other than the front direction, and eliminates the effect of the electromagnetic waves on the human body. On the other hand, an increase in the magnetic field in other directions indicates that the transmission / reception function of the mobile phone does not decrease even when the mobile phone case is attached.

[0046]

[Table 9]

[0047]

[Table 10]

[0048]

[Table 11]

[0049]

[Table 12]

[0050]

[Table 13]

[0051]

[Table 14]

[0052]

[Table 15]

[0053]

[Table 16]

From the above measurement results, taking the data of the measurement distance of 5 cm in the surface direction (c-1) as an example, the electric field / power density without the cover is calculated as follows. Electric field E = 78 ^0.5 = 8.8 than [V / m] P [W / m 2] = E 2/120 π, the power density P = 78/120 π = 0.21 [W / m 2]

As a result of the above calculation, the electric field (without cover): 8.8 [V / m] The electric field (with cover): <1.7 [V / m] At this time, the attenuation rate of the electric field is calculated as follows. Electric field decay rate = (8.8− <1.7) /8.8×100=> 80 [%] Similarly, the power density decay rate is calculated.

From the above measurement results, it is clear that a high electromagnetic wave shielding effect in the direction toward the human body can be obtained in a state where the mobile phone case using the electromagnetic wave shielding material of the present invention is mounted on the mobile phone. On the other hand, the electric field is attenuated in any direction, and the danger of causing malfunction of other devices is avoided.

[0057]

[Effect of the invention]

 As described above, the mobile phone case using the electromagnetic wave shielding material of the present invention has a high electromagnetic wave blocking effect in the direction toward the human body when mounted on the mobile phone, and can be carried even when the mobile phone case is mounted. An excellent effect is obtained in that adverse effects on the human body can be avoided without reducing the transmission / reception function of the telephone.

[Brief description of the drawings]

FIG. 1 is an enlarged view of an electromagnetic wave shielding net used in the present invention.

FIG. 2 is an exploded structural view of an example of the electromagnetic wave shielding material used in the present invention.

FIG. 3 is a perspective view of another example of the electromagnetic wave shielding material used in the present invention.

FIG. 4 is an exploded structural view of still another example of the electromagnetic wave shielding material used in the present invention.

FIG. 5 is an exploded structural view of still another example of the electromagnetic wave shielding material used in the present invention.

FIG. 6 is an external view of the mobile phone case of the present invention.

FIG. 7 is a partially enlarged view of the mobile phone case of FIG. 6;

[Explanation of symbols]

 1, 3 Soft sheet material 2 Electromagnetic wave shielding net 11 Base cloth 13 Surface layer 21 Antenna cap 24 Transparent laminate sheet 31 Adhesive or adhesive sheet 33 Release paper 41 Sheet material A Antenna

Claims (2)

[Utility model registration claims] An electromagnetic wave generated from an antenna in a mobile phone case using an electromagnetic wave shielding material formed by knitting conductive fibers and using a base cloth such as synthetic leather to which the electromagnetic wave shielding material is bonded. A mobile phone case characterized in that an antenna cap having an opening so as not to radiate in the direction of is used in connection with the case. 2. The antenna cap has a cylindrical shape in which the upper part is smaller in diameter than the lower part, and a conductive hook in contact with the antenna, which assists in the emission or reception of radio waves, is provided on the upper opening edge of the antenna cap toward the outside of the telephone. 2. The mobile phone case according to claim 1, wherein the mobile phone case is provided on a mobile phone.