Patents Assigned to TDK
  • Patent number: 5106683
    Abstract: In a magnetic recording medium comprising a magnetic layer of a ferromagnetic powder dispersed in a resin binder and a nonmagnetic substrate for the layer, the magnetic layer contains zine aluminate (ZnAl.sub.2 O.sub.4) powder. The ferromagnetic powder is of chromium dioxide (CrO.sub.2) and the ZnAl.sub.2 O.sub.4 content in the magnetic layer is 0.01-1 wt % on the basis of the weight of the ferromagnetic powder.
    Type: Grant
    Filed: August 7, 1990
    Date of Patent: April 21, 1992
    Assignee: TDK Corporation
    Inventors: Hiroyuki Yamada, Norifumi Kajimoto
  • Patent number: 5107386
    Abstract: A magnetic tape cassette capable of positively and rapidly accomplishing the lock release operation irrespective of the direction of force applied to a lock release mechanism to open a front lid. The cassette includes a lock lever regulating mechanism for regulating movement of a lock lever to permit it to be pivotally moved in a direction perpendicular to the longitudinal direction thereof about a holding section of a projection of the lever. The holding section is formed at a position downward apart from the projection and vertically opposite to a lock pawl engaged with the front lid with the projection being interposed therebetween. The lock lever regulating mechanism is constituted by a combination of a position regulating rib provided at the casing and a guide groove formed at the lock lever.
    Type: Grant
    Filed: May 2, 1990
    Date of Patent: April 21, 1992
    Assignee: TDK Corporation
    Inventors: Kenji Hashizume, Masatoshi Okamura, Haruo Shiba
  • Patent number: 5102030
    Abstract: A method for mounting electronic parts on a printed circuit board by applying an adhesive to a printed board at predetermined positions is provided. A droplet of an acryl-modified resin emulsion adhesive in a predetermined volume is ejected from a nozzle to said board at each of said positions, the adhesive is dried to remove water therefrom to ensure mounting of said parts on said binder and a solder is applied to said adhesive areas. The advantage is that an exact amount of adhesive for retaining each part on the board is obtained by each single droplet and in addition the nozzle is non-contactive to the board.
    Type: Grant
    Filed: July 12, 1991
    Date of Patent: April 7, 1992
    Assignee: TDK Corporation
    Inventors: Jun Tamashima, Masatoshi Ide
  • Patent number: 5098546
    Abstract: Proposal is made for providing a high-performance electrode suitable for use in an oxygen-generating electrolytic process having an outstandingly low oxygen overvoltage and exhibiting high durability in a prolonged run of electrolysis. The electrode consists of an electroconductive substrate of a metal, e.g., titanium, and a multiple composite oxide coating layer thereon consisting of at least one layer of type A composed of iridium oxide and tantalum oxide in an Ir:Ta molar ratio of 40:60 to 79.9:20.1 and at least one layer of type B formed on the type A layer composed of iridium oxide and tantalum oxide in an Ir:Ta molar ratio of 80:20 to 99.9:0.1. A plural number of type A layers and a plural number of type B layers can be alternately laid one on the other so as to improve the mechanical stability of the coating layer on the substrate surface.
    Type: Grant
    Filed: December 13, 1990
    Date of Patent: March 24, 1992
    Assignee: TDK Corporation
    Inventors: Yukio Kawashima, Kazuhide Ohe, Hiroyuki Nakada
  • Patent number: 5097391
    Abstract: In a ceramic multilayer chip capacitor comprising alternately stacked internal electrodes of Ni or Ni alloy and dielectric layers, an oxide layer having a different composition from the dielectric layer is formed on the periphery of each internal electrode. The dielectric layer consists essentially of grains and a grain boundary phase, the percent area of the grain boundary phase being up to 2% of the area of a cross section of the dielectric layer. The capacitor is prepared by alternately stacking Ni or Ni alloy and a dielectric material in layer form, firing and then heat treating the stack under predetermined oxygen partial pressures. The dielectric material is a barium titanate base oxide material. The capacitor has a long effective life.
    Type: Grant
    Filed: October 18, 1990
    Date of Patent: March 17, 1992
    Assignee: TDK Corporation
    Inventors: Takeshi Nomura, Masaaki Ikeda, Shigekazu Sumita, Yukie Nakano, Kousuke Nishiyama, Michio Abe
  • Patent number: 5097369
    Abstract: A magnetic head has a slider provided with reading/writing elements wherein the slider has a recessed portion for generating a negative pressure at a surface so that the bottom surface of the recessed portion is slanted at a predetermined grade toward the surface at the side of an air in-flowing end, and the bottom surface terminates at an end of the slider at the side of an air discharging end.
    Type: Grant
    Filed: September 5, 1990
    Date of Patent: March 17, 1992
    Assignee: TDK Corporation
    Inventor: Mikio Matsuzaki
  • Patent number: 5094898
    Abstract: A magnetic recording disk comprising a rigid substrate and a magnetic layer of the continuous thin film type predominantly composed of .gamma.-Fe.sub.2 O.sub.3 shows high durability, especially CSS durability when the magnetic layer has specific peak area ratios in an X-ray diffraction chart thereof, the surface roughness of the substrate and medium surface is controlled to desired ranges, and a lubricating film of a perfluoro derivative of poly(n-propylene oxide) with a specific molecular weight is used. Reliable recording/reproduction can be conducted on the magnetic recording disk using a flying magnetic head.
    Type: Grant
    Filed: June 21, 1990
    Date of Patent: March 10, 1992
    Assignee: TDK Corporation
    Inventors: Haruyuki Morita, Yasufumi Uno, Joichiro Ezaki
  • Patent number: 5094897
    Abstract: A magnetic recording disk comprising a rigid substrate and a magnetic layer of the continuous thin film type is durable and exhibits good electromagnetic properties when the magnetic layer predominantly composed of .gamma.-Fe.sub.2 O.sub.3 has specific peak area ratios in an X-ray diffraction chart thereof. Inclusion of .alpha.-Fe.sub.2 O.sub.3 in the magnetic layer is also effective. Reliable recording/reproduction can be conducted on the magnetic recording disk using a flying magnetic head.
    Type: Grant
    Filed: April 26, 1990
    Date of Patent: March 10, 1992
    Assignee: TDK Corporation
    Inventors: Haruyuki Morita, Monjiro Momoi, Kazumasa Fukuda
  • Patent number: 5094896
    Abstract: A magnetic recording disk comprising a rigid substrate and a magnetic layer of the continuous thin film type is durable and exhibits good electromagnetic properties and frequency response when the magnetic layer is predominantly composed of .gamma.-Fe.sub.2 O.sub.3 and has a resistivity of 0.03 to 3 .OMEGA.-cm. Reliable recording/reproduction can be conducted on the magnetic recording disk using a flying magnetic head.
    Type: Grant
    Filed: April 26, 1990
    Date of Patent: March 10, 1992
    Assignee: TDK Corporation
    Inventors: Haruyuki Morita, Monjiro Momoi, Kazumasa Fukuda
  • Patent number: 5092758
    Abstract: A disc molding apparatus capable of satisfactorily accomplishing the release of a molded disc without any trouble to eliminate deformation of the disc during the release and improve quality, reliability and productivity of the disc. In the disc molding apparatus, an air inlet port is provided in proximity to an outer stamper holder of an outer ring for supplying air toward a central region of a disc molded in a cavity of a mold body from a periphery of the disc and a communication passage communicating with the air inlet passage is provided at the outer ring, so that air may be more uniformly blown against the disc during the release of the disc from a stamper.
    Type: Grant
    Filed: May 14, 1990
    Date of Patent: March 3, 1992
    Assignee: TDK Corporation
    Inventors: Toshifumi Tanaka, Yasuo Ohira, Toshihiko Ishida
  • Patent number: 5091814
    Abstract: A disk cartridge comprises a casing formed by combining upper and lower half casings so as to rotatably receive therein a disk-like magnetic medium with a center hub which is connectable to a magnetic recording/reproducing device and a hub-position determining annular rib formed at the central portion of the inner surface of the upper half casing so as to define a rotating region for the hub, wherein the hub-position determining annular rib is discontinuous.
    Type: Grant
    Filed: November 23, 1990
    Date of Patent: February 25, 1992
    Assignee: TDK Corporation
    Inventors: Masaru Ikebe, Haruo Shiba, Morimasa Sasaki
  • Patent number: 5091820
    Abstract: A ceramic piezoelectric, includes a thick core formed of a sintered ceramic material, and a pair of electrodes formed on opposing end faces of the core, wherein the electrodes are a reduced form of the ceramic material of the core. The electrodes may also be a reduced layer of an oxide formed on the ceramic material of the core.
    Type: Grant
    Filed: November 3, 1989
    Date of Patent: February 25, 1992
    Assignee: TDK Corporation
    Inventors: Shouichi Iwaya, Munemitsu Hamada, Hitoshi Masumura
  • Patent number: 5091810
    Abstract: This invention provides a floating type magnetic head comprising a slider which has at least two rail-like floating parts, and a head core attached on a side of the slider. The magnetic head is characterized in that the head core is attached to the slider in a manner a window thereof for wiring protrudes from the rear end of the slider or the slider end facing downstream in the advancing direction of a magnetic recording medium or a side of the slider adjacent to the window is partially cut out on the rear end thereof. Such structure simplifies winding operation. Another feature of this invention magnetic head lies in that the magnetic gap of the head core is positioned at outermost location of the head to thereby increase recording capacity on a recording medium.
    Type: Grant
    Filed: May 25, 1990
    Date of Patent: February 25, 1992
    Assignee: TDK Corporation
    Inventors: Masao Kakizaki, Yoshihito Kobayashi, Hiroshi Yagi
  • Patent number: 5089344
    Abstract: A magnetic recording medium whose magnetic layer formed on a base comprises a magnetic powder and a binder which contains a tertiary amine and uses 1,4-cyclohexanedimethanol as a chain extender. The magnetic powder is preferably of CrO.sub.2. The medium is made by mixing and dispersing the magnetic powder in a binder which consists of a reaction product of (A) a polyester which is a reaction product of a diol selected from among ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentadiol, and 1,6-hexanediol, and adipic acid, (B) a chain extender consisting of 1,4-cyclohexanedimethanol, (C) an aliphatic or aromatic diisocyanate in an amount substantially equal to the combined molar amount of the polyester and the chain extender, and (D) a tertiary amine, and applying the resulting magnetic coating material to a base.
    Type: Grant
    Filed: July 31, 1989
    Date of Patent: February 18, 1992
    Assignee: TDK Corporation
    Inventors: Kazunori Tamazaki, Hitoshi Azegami, Kazuhiro Kuroda
  • Patent number: 5089314
    Abstract: A carrier tape for electronic circuit elements adapted to be provisionally held on printed circuit boards prior to fixing of them on said printed circuit boards by soldering, comprises a flexible tape body extending in a longitudinal direction, and adhesive means applied with respect to the tape body and for serving the purpose of provisionally holding of electronic circuit elements on printed circuit boards, the adhesive means being formed of a material which exhibits adhesion upon being heated. The adhesive means is formed of a polymeric material which exhibits adhesion upon being heated. The carrier tape further includes electronic circuit elements held with respect to the tape body at equal intervals in a row in the longitudinal direction of the tape body through the adhesive means, thereby constituting an electronic circuit element series.
    Type: Grant
    Filed: February 15, 1990
    Date of Patent: February 18, 1992
    Assignee: TDK Corporation
    Inventors: Sho Masujima, Hiroshi Yagi, Atsuzo Tamashima, Masakazu Kamoshida
  • Patent number: 5084962
    Abstract: An automatic electronic component mounting apparatus for automatically mounting electronic components on the printed circuit board includes an electronic component supply mechanism for supplying an electronic component to a predetermined position, at least one mounting head movable in a Y direction, a first controlling mechanism for moving the mounting head in the Y direction, a movable frame movable in an X direction, a second controlling mechanism for moving the movable frame in the X direction and controlling the position of the movable frame in the X direction, a support base supported to the movable frame, and a table carrying a printed circuit board and turnable in a .theta. direction. The table is rotatably supported on the support base so that when the X directional position of the movable frame is controlled by the second controlling mechanism, the X directional position of the table is also controlled. A third controlling mechanism is provided for controlling a .theta.
    Type: Grant
    Filed: August 24, 1989
    Date of Patent: February 4, 1992
    Assignee: TDK Corporation
    Inventors: Kuniaki Takahashi, Koji Kudo, Shinichi Araya, Hitoshi Nakayama
  • Patent number: 5084426
    Abstract: A semiconductive ceramic composition capable of permitting its resistance-temperature characteristics and resistance to be controlled as desired and a firing temperature of the composition to be lowered to a degree sufficient to facilitate the mass-production at a low cost. The composition contains a main component consisting of SrO, PbO and TiO.sub.2 and is subjected to firing in an oxidizing atmosphere. The composition may contain at least one of SiO.sub.2 and M as a minor component. A variation in amount of the main and minor components permits characteristics and properties of the composition to be varied as desired.
    Type: Grant
    Filed: July 13, 1989
    Date of Patent: January 28, 1992
    Assignee: TDK Corporation
    Inventors: Shoichi Iwaya, Hitoshi Masumura, Haruo Taguchi, Munemitsu Hamada, Tomohiro Sogabe, Shigeya Takahashi, Hiroyuki Satoh
  • Patent number: 5082197
    Abstract: A tape cassette is provided which is so constructed that a plurality of weighting members are fittedly held in fitting apertures or recesses of a casing formed at corners of the casing in a detachable manner while being exposed at part thereof on a surface of the casing. Such construction of the cassette not only permits the cassette to exhibit optimum vibration-damping properties to ensure satisfactory recording and reproducing of the cassette and contributes an improvement in mechanical strength of the cassette but provides the cassette with a variation in design sufficient to exhibit good aesthetic properties, to thereby increase a merchandise value of the cassette.
    Type: Grant
    Filed: July 3, 1989
    Date of Patent: January 21, 1992
    Assignee: TDK Corporation
    Inventors: Takateru Satoh, Kimio Tanaka, Haruo Shiba, Noboru Uemura, Kenkichi Akaoka
  • Patent number: 5082808
    Abstract: A ceramic material for use as artificial bone and dental root is provided which takes the form of a composite sintered body comprising crystalline calcium phosphate grains as a matrix and inorganic whiskers dispersed therein. An intermediate layer containing elements in either one or both of the whiskers and the grains intervenes between the whiskers and the grains. The material has physical toughness and strength as well as biomedical affinity. The material is prepared by mixing calcium phosphate and a whisker-forming material or whiskers and sintering the mixture at a temperature of 800.degree. to 1600.degree. C., followed by slow cooling to allow formation of the intermediate layer.
    Type: Grant
    Filed: October 4, 1990
    Date of Patent: January 21, 1992
    Assignee: TDK Corporation
    Inventors: Tohru Nonami, Nobuo Yasui
  • Patent number: 5082685
    Abstract: A treatment, typically plasma treatment apparatus comprises a plasma creating chamber adapted to create a plasma therein, a treating chamber in communication with the plasma creating chamber through an electrode for drawing electron beams from the plasma, an input conduit coupled to the treating chamber for introducing a reaction gas therein, and directive means associated with the input conduit for imparting directivity to the reaction gas. With the apparatus, plasma treatment, typically plasma CVD or plasma etching is carried out on an article in the chamber by forming a high density region of the reaction gas substantially perpendicular to the electron beams in the chamber.
    Type: Grant
    Filed: July 19, 1990
    Date of Patent: January 21, 1992
    Assignee: TDK Corporation
    Inventor: Hisao Morooka