JP5104362B2 - Electromagnetic shielding partition - Google Patents

Description

  The present invention relates to a transparent partition for shielding electromagnetic waves from an MRI apparatus that generates electromagnetic waves.

  In recent years, apparatuses that generate strong electromagnetic waves such as MRI (Magnetic Resonance Imaging) apparatuses have become widespread in medical facilities. Since electronic devices such as OA / communication devices are indispensable around such devices, electronic devices such as OA / communication devices are caused by electromagnetic waves from devices that generate strong electromagnetic waves such as MRI devices. There are concerns about cases of malfunctions and noise.

  For this reason, in the place where the MRI apparatus is installed, the periphery of the apparatus is often surrounded by an opaque metal panel or a panel mixed with a magnetic material.

  In recent years, in office buildings and stores, in order to eliminate the feeling of blockage of sealed rooms, transparent panels are often used for partitioning, and in medical institutions, transparent partitioning is required in order to eliminate the blockage, A transparent partition is also required for installation of the MRI apparatus.

  Since the electromagnetic waves generated by the MRI apparatus are quite strong, the electromagnetic wave shielding performance (hereinafter simply referred to as shielding performance) is required to be 100 dB or more at a frequency range of 21.3 MHz.

  As a transparent electromagnetic shielding panel used for an opening of a building, there is one in which a wire mesh is inserted into an interlayer film of laminated glass. Electromagnetic shielding with a wire mesh can improve the shielding performance by using two or more wire meshes, but when the wire meshes are overlapped, moire fringes are generated, and the metal wire of the wire mesh is opaque. The problem of disappearing arises. Further, an electromagnetic shielding glass using two metal meshes, which has a transparent property and has a shielding performance of 100 dB or more, has not been known.

  For example, Patent Document 1 discloses an electromagnetic shielding glass that eliminates moire fringes using a 65-150 mesh wire mesh and a 10-50 mm mesh metal mesh, and a copper mesh 100 mesh wire mesh and a line spacing of 15 mm. An electromagnetic shielding glass having a shielding performance of 66 dB using a turtle shell-shaped net is described.

Further, Patent Document 2 describes an electromagnetic shielding glass having a shielding performance of 92 dB at a frequency of 1 MHz, using a double-layered glass configuration in which two sheets of laminated glass with a metal mesh inserted into an intermediate film are used and the interval between the metal meshes is 12 mm. ing.
JP 2000-114769 A Japanese Patent Laid-Open No. 9-321484

  An object of the present invention is to provide a transparent electromagnetic shielding partition that shields electromagnetic waves generated by an MRI apparatus by 100 dB or more and has excellent transparency.

The electromagnetic shielding partition of the present invention is an electromagnetic shielding partition formed by opposingly arranging two metal mesh-inserted laminated glasses, and the wire mesh is a metal wire coated with a black dyed oxide film, and the mesh of the wire mesh is 60-150 mesh, the distance between the two wire meshes is 50-300 mm, the wire mesh protrudes from the edge of the laminated glass and is folded back to the surface of the laminated glass, and the black mesh oxidation of the folded wire mesh An electromagnetic shielding partition characterized in that a conductive sealing material is provided between the coating and the grounded metal frame.

  The electromagnetic shielding partition according to the present invention sufficiently shields the electromagnetic waves generated by the MRI apparatus, has excellent transparency, and can provide an electromagnetic shielding partition with an open feeling.

  The electromagnetic shielding partition according to the present invention is an electromagnetic shielding partition formed by arranging two wire mesh-inserted laminated glasses 21 and 22 to face each other as shown in FIG.

  The metal mesh insertion laminated glass 21 has a metal mesh 9 inserted between two intermediate films 5 and 6, and the metal mesh insertion laminated glass 22 has a metal mesh 10 inserted between two intermediate films 7 and 8. Become.

  The metal mesh 9 inserted between the intermediate films 5 and 6 and the metal mesh 10 inserted between the intermediate films 7 and 8 are made of a metal wire obtained by coating a black dyed oxide film on an iron wire, a copper wire, a nickel wire, or the like. A plain weave or twill weave with a wire diameter of 0.10 mm and an aperture of 0.41 mm to 150 mesh (wire diameter of 0.060 mm and an aperture of 0.109 mm) is preferably used.

A metal wire coated with a black-dyed oxide film is preferable because it prevents the presence of a wire mesh from being visually recognized by reflection.

  When the wire mesh is smaller than 60 mesh, the aperture ratio is small, the metal wire is thick, and preferable transparency cannot be obtained. Moreover, since the shielding performance of 100 dB or more cannot be obtained, it is preferable to use a wire mesh of 60 mesh or more.

  On the other hand, if it is larger than 150 mesh, it becomes difficult to obtain a shielding performance of 100 dB or more.

  For the glass plates 1, 2, 3, and 4, a float plate glass having a thickness of 3 to 20 mm is preferably used, and the interval d between the metal nets 9 and 10 may be set to 50 mm or more at which no moire fringes are visually recognized. In order to obtain the above shielding performance, the thickness is preferably 60 mm or more.

Even if the distance d between the metal meshes 9 and 10 exceeds 300 mm and is about 1 mm , the shielding performance is 100 dB or more. However, in the space between the metal mesh insertion laminated glasses 21 and 22, the electromagnetic shielding performance is smaller than 100 dB and is useless. Since it becomes space, it was set to 300 mm or less.

  In consideration of transparency and shielding performance, the distance d between the metal meshes 9 and 10 is more preferably 100 to 250 mm.

  The interval d between the metal nets 9 and 10 can be set by positioning the metal net insertion laminated glasses 21 and 22 at a predetermined interval using a spacer 19. When a metal spacer is used for the spacer 19, resin backup materials 15 and 16 are used between the spacer 19 and the wire mesh insertion laminated glasses 21 and 22, and the spacer 19 and the wire mesh insertion laminated glasses 21 and 22 are used. It is preferable not to make direct contact.

  The spacer 19 may be made of a resin or wooden spacer, and the backup materials 15 and 16 may not be used.

  It is preferable that the metal meshes 9 and 10 are grounded. The metal meshes 9 and 10 protrude from the edges of the metal mesh insertion laminated glasses 21 and 22 and are folded back so as to be in contact with the surfaces of the metal mesh insertion laminated glasses 21 and 22. It is preferable that the conductive sealing materials 11 and 12 are packed between the metal frame 13 and the metal pressing edge 14. The metal frame 13 and the metal pressing edge 14 are preferably grounded (not shown).

  Further, the metal mesh used for the wire mesh is not peeled off, but is in contact with the conductive sealing materials 11 and 12 so that the metal meshes 9 and 10 and the conductive sealing materials 11 and 12 are in direct contact. It is better not to peel off the black-dyed oxide film.

Example 1
The electromagnetic shielding partition for EMI shown in FIG. 1 was produced.

  A metal mesh 9 was sandwiched between the intermediate films 5 and 6, and a metal mesh insertion laminated glass 21 in which the glass plates 1 and 2 were laminated using the intermediate films 5 and 6 was produced.

  Further, the metal mesh 10 was sandwiched between the intermediate films 7 and 8, and the metal mesh insertion laminated glass 22 in which the glass plates 3 and 4 were laminated using the intermediate films 7 and 8 was produced.

  Further, an aluminum spacer 19 was used so that the distance d between the metal nets 9 and 10 was 200 mm, and the laminated glass 21 and 22 with the metal nets were arranged to face each other to form an electromagnetic shielding partition for EMI.

  Silicone backup materials 15 and 16 were inserted between the metal mesh insertion laminated glasses 21 and 22 and the spacer 19 so that the metal mesh insertion laminated glasses 21 and 22 and the spacer 19 did not contact each other.

  The glass plates 1, 2, 3, and 4 were float glass plates having a thickness of 5 mm, and the intermediate films 5, 6, 7, and 8 were polyvinyl butyral membranes having a thickness of 0.37 mm.

  The wire nets 9 and 10 were made by plain weaving of an iron wire on which a black dyed oxide film was formed with 100 mesh (wire diameter 0.1 mm, wire spacing 0.15 mm).

  Furthermore, the metal meshes 9 and 10 are 25 mm long from the edge of the laminated glass, and are folded back on the surface of the metal mesh-inserted laminated glasses 21 and 22 on the opposite side of the air layer 18 so as to have conductivity. And a black dyed oxide film.

  Further, the sealing material 11 is in contact with the metal frame 13 and the sealing material 12 is in contact with the metal pressing edge 14, and the metal frame 13 and the metal pressing edge 14 are grounded (not shown). .

  The electromagnetic shielding partition of this example had sufficient performance as an electromagnetic shielding partition for EMI with an electromagnetic shielding performance of 110 dB against electromagnetic waves in the frequency range of 10 to 100 MHz.

  Furthermore, as shown in FIG. 2, the electromagnetic shielding partition produced in this example did not observe moire interference fringes due to the wire meshes 9 and 10, and had good transparency.

Example 2
A plain weave wire mesh of mesh 60 made using iron wire is used for the wire mesh 9, and a plain weave wire mesh of mesh 100 made using iron wire is used for the wire mesh 10, and the distance d between the two wire meshes 9 and 10 is set to 60 mm. Other than that, an electromagnetic shielding partition for MRI was produced in the same manner as in Example 1.

  The electromagnetic shielding partition of this example had sufficient performance as an electromagnetic shielding partition for EMI with an electromagnetic shielding performance of 108 dB against electromagnetic waves in the frequency range of 10 to 100 MHz.

  Further, similarly to Example 1, moire interference fringes due to the metal nets 9 and 10 were not observed, and the transparency was good.

Example 3
A plain weave wire mesh of mesh 150 made using iron wire is used for the wire mesh 9, and a plain weave wire mesh of mesh 100 made using iron wire is used for the wire mesh 10, and the distance d between the two wire meshes 9 and 10 is set to 300 mm. Other than that, an electromagnetic shielding partition for MRI was produced in the same manner as in Example 1.

  The electromagnetic shielding partition of this example had sufficient performance as an electromagnetic shielding partition for EMI with an electromagnetic shielding performance of 115 dB against electromagnetic waves in the frequency range of 10 to 100 MHz.

  Further, as in Example 1, moire interference fringes due to the metal nets 9 and 10 were not observed, and the transparency was good.

It is a schematic sectional drawing of the electromagnetic shielding partition for EMI of this invention. The electromagnetic shielding partition produced in Example 1

Explanation of symbols

1, 2, 3, 4 Glass plate 5, 6, 7, 8 Intermediate film 9, 10 Wire mesh 11, 12 Conductive sealing material 13 Metal frame 14 Metal pressing edge 15, 16 Backup material 17, 18 Setting block 19 Spacer 21,22 Wire mesh insertion laminated glass

Claims (1)

An electromagnetic shielding partition formed by opposingly arranging two metal mesh-inserted laminated glasses, wherein the metal mesh is a metal wire coated with a black-dyed oxide film, and the mesh of the metal mesh is 60 to 150 mesh, The interval between the metal meshes is 50 to 300 mm, the metal mesh protrudes from the edge of the laminated glass, is folded back to the surface of the laminated glass, and is made of metal that is grounded with the black dyed oxide film of the folded metallic mesh. An electromagnetic shielding partition, wherein a conductive sealing material is provided between the frame body and shields electromagnetic waves from the MRI apparatus .

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