公开(公告)号：JPH05291782A

公开(公告)日：1993-11-05

申请号：JP11541992

申请日：1992-04-08

Applicant: NEC CORP ,  TODA KOGYO CORP ,  NEC ENVIRONMENT ENG LTD

Inventor： HATAKEYAMA KENICHI ,  HANKOU EIJI ,  YAMAMOTO SHIGEHISA ,  YOSHIUCHI AKIRA

IPC: H05K9/00

Abstract: PURPOSE:To stabilize electric wave absorbing performance and then reduce weight by mixing three types, namely a base material, a filling substance, and a conductive substance, simultaneously or constituting an electronic absorber by mixing either two types and then mixing the remaining one type to the mixture. CONSTITUTION:A base material such as a paint, rubber, and epoxy resin, a non-conductive and non-magnetic granular object such as granular polyetylene, expanded stylene beads, and glass ball, and a conductive material such as a conductive particle and a conductive fiber are mixed simultaneously or two types, namely a base material such as epoxy resin and a filling substance such as expanded styrene beads with a diameter of 6mm are mixed and then the conductive material such as conductive particle and conductive fiber are mixed to these two types, thus constituting an electric wave absorber. In this manner, a secondary surface is constituted on purpose and then a conductive particle, a conductive fiber, or a magnetic particle is laid out on the secondary surface, thus maldistributing the particle and hence stabilizing electric wave absorbing performance.

公开(公告)号：JPH04116999A

公开(公告)日：1992-04-17

申请号：JP23743990

申请日：1990-09-07

Applicant: NEC CORP ,  MIYAGI NIPPON DENKI KK

Inventor： HARADA TAKASHI ,  INOMATA MASAYUKI ,  HATAKEYAMA KENICHI ,  FUJIWARA NOBORU ,  MASUDA NORIO

IPC: H05K9/00

Abstract: PURPOSE:To obtain a high-electromagnetic-shielding-ability enclosure by fixing a magnetic material to the cord drawing openings of the electrical and electronic equipment mounting enclosure. CONSTITUTION:A magnetic material 3 is fixed to the outside of an enclosure. An unnecessary electromagnetic wave leaking to the outside of the enclosure through its openings 2 is reflected by a common mode choke including the magnetic material 3, a cable, and a code, therefore, it is not radiated to the outside. The area of the openings is preferably small to enhance the leakage suppression effect. The magnetic material 3 can be removed from the openings of the enclosure and divided into a plurality of pieces to divide the openings, therefore, the cable and cord can be passed through the openings even if the openings are smaller than a connector and a socket.

公开(公告)号：JPH03112196A

公开(公告)日：1991-05-13

申请号：JP25108789

申请日：1989-09-27

Applicant: NEC CORP

Inventor： HARADA TAKASHI ,  HATAKEYAMA KENICHI

IPC: H05K9/00

Abstract: PURPOSE:To improve shielding effect by coating a large number of arranged hollow opposing wall surfaces produced by combining plates of improved conductivity in grid shape with a required material. CONSTITUTION:Opposing wall surfaces of cavities 2 of a structured body 4 which is formed by a number of arranged cavities 2 which are produced by combining a metal plate 1 of improved conductivity in grid shape are coated with a sheet 3 made of a material of high permeability. Therefore, by reducing an opening area and increasing depth, shielding effect can be enhanced without extending the length of a waveguide path, thus further enhancing the shielding effect with the same opening area and depth.

公开(公告)号：JPH02250397A

公开(公告)日：1990-10-08

申请号：JP7212389

申请日：1989-03-23

Applicant: NEC CORP

Inventor： HATAKEYAMA KENICHI ,  SAWATO EIKICHI

IPC: H05K9/00

Abstract: PURPOSE:To shield an electromagnetic wave which leaks out of a clearance section of a box body by providing a board of metal box body with a magnetic substance whose permeability has an incline which increases from an outer side of the box body toward an inner side thereof. CONSTITUTION:A metal box body board A which covers a metal box body B is provided with a magnetic substance D whose permeability has an incline which increases from an outer side of the box body toward an inner side thereof. Therefore, if a ratio of space occupied by the magnetic substance D is made larger inside the box body in correspondence with the clearance of an overlapped section C, the gradient of permeability at the clearance section can be acquired equivalently. As for an influence of the gradient of permeability concerning prevention of leakage from the clearance, strictly speaking, a propagation equation should be derived from the Maxwell's equations in a state where the permeability mu is a function of the position; however, it can be qualitatively explained by that the propagation velocity (v) is in inversely proportion to sq. rt. mu. Thereby, leakage of an electromagnetic wave from the clearance section of the box body can be restrained.

公开(公告)号：JPS63194400A

公开(公告)日：1988-08-11

申请号：JP2664387

申请日：1987-02-06

Applicant: NEC CORP

Inventor： HATAKEYAMA KENICHI ,  INUI TETSUJI

IPC: H05K9/00

公开(公告)号：JPS63168093A

公开(公告)日：1988-07-12

申请号：JP31182986

申请日：1986-12-29

Applicant: NEC CORP

Inventor： INUI TETSUJI ,  HATAKEYAMA KENICHI ,  YOSHIUCHI AKIRA

IPC: H05K9/00 ,  H01Q17/00

公开(公告)号：JPS6314498A

公开(公告)日：1988-01-21

申请号：JP15824386

申请日：1986-07-04

Applicant: NEC CORP

Inventor： HARADA TAKASHI ,  HATAKEYAMA KENICHI

IPC: H05K9/00

公开(公告)号：JPS6240799A

公开(公告)日：1987-02-21

申请号：JP18067885

申请日：1985-08-16

Applicant: NEC CORP

Inventor： HATAKEYAMA KENICHI ,  HARADA TAKASHI ,  INUI TETSUJI

IPC: H05K9/00 ,  E04B1/62 ,  H01Q17/00

公开(公告)号：JPS61216408A

公开(公告)日：1986-09-26

申请号：JP5783185

申请日：1985-03-22

Applicant: NEC CORP

Inventor： HATAKEYAMA KENICHI ,  INUI TETSUJI

IPC: H01Q17/00 ,  H01F1/00 ,  H05K9/00

Abstract: PURPOSE:To reduce the effect of a diamagnetic field by alternately laminating magnetic material layers and dielectric layers. CONSTITUTION:A magnetic material layer 1 is manufactured by alternately laminating magnetic material layers 1 and dielectric layers 2, widths (a), (b) are determined from the viewpoint of manufacture or use, and a/c>100 and b/c>100 hold regarding the thickness (c). The magnetic field components of electromagnetic waves projecting in the direction of an (x) axis runs parallel with a Y-Z surface, a sheet surface, in the sheet of the magnetic material layer 1, and magnetic anisotropy in the sheet surface is reduced and magnetoplumbite group ferrite is employed.

公开(公告)号：JPS6137832A

公开(公告)日：1986-02-22

申请号：JP16014484

申请日：1984-07-30

Applicant: Nec Corp ,  Seitetsu Kagaku Co Ltd

Inventor： OBAYASHI SHIGEJI ,  NAKAMURA MORIO ,  HATAKEYAMA KENICHI ,  INUI TETSUJI

IPC: H05K9/00 ,  C08K3/18 ,  C08K3/22 ,  C08K7/00 ,  C08K7/02 ,  C08K13/04 ,  C08L7/00 ,  C08L21/00 ,  C08L21/02 ,  H01B1/20

Abstract: PURPOSE: A radio wave absorbing material which can effectively absorb radio waves regardless of their directions of incidence, prepared by making a mixture comprising a powdered elastomer, a ferrite powder and an electroconductive fiber into a sheet.
CONSTITUTION: 100pts.wt. powdered elastomer (e.g., chloro-sulfonated polyethylene powder or nitrile rubber powder) is mixed with 100W500pts.wt. ferrite powder (BaO.6Fe
2 O
3 powder) and 2W150pts.wt. 0.5W5mm-long electroconductive fiber (e.g., brass fiber) in a state in which substantially no shearing force is exerted on the mixture. A sheet which is used as a radio wave absorbing material is obtained by molding the obtained mixture under application of heat and pressure.
COPYRIGHT: (C)1986,JPO&Japio

Abstract translation: 目的：通过将粉末状弹性体，铁氧体粉末和导电性纤维的混合物制成片材而制备的无线电波无论波形如何，都能有效地吸收无线电波。 构成：100pts.wt。 粉末弹性体（例如氯磺化聚乙烯粉末或丁腈橡胶粉末）与100-500pts.wt。 铁氧体粉末（BaO.6Fe2O3粉末）和2-150pts.wt。 0.5-5mm长的导电纤维（例如黄铜纤维），其中基本上不对剪切力施加剪切力。 用作无线电波吸收材料的片材是通过在加热和加压下加热所得混合物而得到的。