Patents Assigned to TDK
  • Patent number: 4976356
    Abstract: A method of optically checking the appearances of chips and sorting the chips comprises the steps of feeding chips onto chip-passage body to cause the chips to run on the chip-passage body in a predetermined direction; during the running of the chips on the chip-passage body, individually separating the chips to stop the chips one by one at each of two predetermined checking positions; irradiating light obliquely and straightly with respect to a chip at one of the predetermined checking positions to pick up an optical image of one of undersurface and top surface sides of the chip as a video signal by means of a first TV camera; irradiating light obliquely and straightly with respect to the chip at the other of the predetermined checking positions to pick up an optical image of the other of the undersurface and top surface sides of the chip as a video signal by means of a second TV camera; sending the video signals to image processing sections, each of which includes at least an analog-to-digital conversion un
    Type: Grant
    Filed: February 28, 1989
    Date of Patent: December 11, 1990
    Assignee: TDK Corporation
    Inventors: Touru Mizuno, Yasuhiko Kitajima
  • Patent number: 4977475
    Abstract: A disk cartridge includes upper and lower half casings to be assembled to form a hard casing, a magnetic disk held in the casing in a rotatable manner and lining members attached to the inner surfaces of the upper and lower half casings, wherein the lining member has a laminated structure which includes an attracting layer as a base layer for attracting dust and a smooth layer having a large number of apertures which is laminated on at least one surface of the base layer.
    Type: Grant
    Filed: March 23, 1989
    Date of Patent: December 11, 1990
    Assignee: TDK Corporation
    Inventors: Haruo Shiba, Masaru Ikebe
  • Patent number: 4973934
    Abstract: A PTC thermistor device including a PTC thermistor element of a circular configuration, and a casing made of a plastic material. The casing has a substantially parallelepipedic body portion and a projecting portion having a pair of parallel side surfaces and a planar top surface. A terminal fitting is provided in contact with the PTC element and has plug portions projecting from the casing at the opposite sides of the projecting portion. The plugs has projecting lengths which are not higher than the height of the projecting portion of the casing.
    Type: Grant
    Filed: June 15, 1989
    Date of Patent: November 27, 1990
    Assignee: TDK Corporation
    Inventors: Kazuo Saito, Michikazu Takeuchi
  • Patent number: 4973012
    Abstract: A magnetic tape cassette comprises a casing consisting of upper and lower half casings, reel hubs contained in the casing so as to be rotatable, a magnetic tape wound around on the reel hubs, a support pin projecting from the casing, a pad provided near an area of rotation of the hub, the pad having an intermediate portion turnably supported by the support pin and an end portion for pushing the magnetic tape to guide rollers and/or guide poles provided at the area where the magnetic tape runs, and a rib projecting from the casing and having the free end which is in contact with the other end portion of the pad so that the one end portion of the pad is urged to a side wall of the casing.
    Type: Grant
    Filed: April 13, 1989
    Date of Patent: November 27, 1990
    Assignee: TDK Corporation
    Inventors: Kenji Hashizume, Masatoshi Okamura, Takateru Satoh
  • Patent number: 4972191
    Abstract: A flat wave absorber having a conductive plate, a dielectric plate on the conductive plate, and, a ferrite plate on said dielectric plate, provides a wide operational frequency range from 30 MHz to 1 GHz with excellent attenuation characteristics, and an anechoic chamber mounting said wave absorber on inside surface of the chamber is provided. Thickness of said dielectric plate is less than 25 mm, the thickness of said ferrite plate is less than 7.5 mm, and real part of complex impedance of said ferrite plate on the conductive plate is less than 1.0 and close to 1.0. Said ferrite plate is attached to said dielectric plate in the form of tiles.
    Type: Grant
    Filed: July 24, 1989
    Date of Patent: November 20, 1990
    Assignee: TDK Corporation
    Inventors: Ken Ishino, Taro Miura, Takashi Watanabe, Masashi Katsumata
  • Patent number: 4966031
    Abstract: In a vibration sensor including a base member shaped in the form of a sleeve having a structure for installation on an object of measurement, a piezoelectric conversion portion put onto the periphery of the same, and lead wire member connecting the same with the outside of the sensor, the present invention is characterized in that the piezoelectric conversion portion and a portion of the lead wire member are integrally covered with polyamide resin and it is thereby formed into a case member. The present invention with the above described arrangement makes most of the characteristics of the polyamide resin having a strong crystalline polymer structure, whereby the frequency response characteristic of the vibration sensor is improved against thermal stress.
    Type: Grant
    Filed: January 6, 1989
    Date of Patent: October 30, 1990
    Assignee: TDK Corporation
    Inventor: Kazuo Mochizuki
  • Patent number: 4965690
    Abstract: A tape cassette including an upper and a lower half housing sections each of which is comprised of an inner housing layer and an outer housing layer formed integrally on the outer surface of the inner layer, the upper and lower half housing sections containing a tape and reels on which the tape is wound or unwound inside the inner housing layers and having guide members located close to the front end of the housing to guide the tape, characterized in that said outer housing layers are molded from a thermoplastic elastomeric material to impart anti-shock or vibration property.
    Type: Grant
    Filed: December 21, 1988
    Date of Patent: October 23, 1990
    Assignee: TDK Corporation
    Inventors: Kimio Tanaka, Haruo Shiba
  • Patent number: 4965483
    Abstract: A piezoelectric buzzer comprising a case having the shape of a bottomed cylinder, a piezoelectric diaphragm fixedly disposed within the case, a cover plate fitted in the open end of the case, and terminals integrally combined with the cover plate and each having one end in contact with the piezoelectric diaphragm and the other end projecting outside from the cover plate. Since the cover plate and the terminals are combined together by insert molding, no gap is formed between the cover plate and the terminals, no sealing work for sealing gaps between the cover plate and the terminals is necessary, the manufacturing process is simplified, and the piezoelectric element is not exposed to the external atmosphere.
    Type: Grant
    Filed: March 13, 1989
    Date of Patent: October 23, 1990
    Assignee: TDK Corporation
    Inventors: Toshio Abe, Seiichi Takahashi, Masaharu Kamihara, Hitoshi Saito, Seizo Tanaka, Yasuyuki Suzuki
  • Patent number: 4956114
    Abstract: A ferrite composition comprising ferrite, borosilicate glass, and optionally boron oxide can be fired at a relatively low temperature of up to 950.degree. C. into a sintered body having improved mechanical strength and electromagnetic properties. The sintered ferrite body is used to form a chip inductor. The inductor is combined with a capacitor to form a composite LC part.
    Type: Grant
    Filed: June 29, 1988
    Date of Patent: September 11, 1990
    Assignee: TDK Corporation
    Inventors: Hideo Watanabe, Yoichi Kanagawa, Takashi Suzuki, Takeshi Nomura
  • Patent number: 4952902
    Abstract: A thermistor material comprising, in sintered form, (A) a matrix comprising aluminum oxide, silicon oxide, or the oxide of an element belonging to Group 2A in the Periodic Table, and (B) a conductive path forming substance comprising silicon carbide and/or boron carbide, wherein the volume ratio of silicon carbide to the matrix is up to about 1.24 is stable at elevated temperatures of 400.degree.-800.degree. C.
    Type: Grant
    Filed: October 16, 1989
    Date of Patent: August 28, 1990
    Assignee: TDK Corporation
    Inventors: Yukio Kawaguchi, Tohru Kineri
  • Patent number: 4950535
    Abstract: A magnetic recording medium, comprising a substrate, a ferromagnetic film layer formed on the surface of said substrate, and a back coating layer deposited on the other surface of said substrate and formed of a mixture produced by dispersing a powdered non-magnetic substance in a binder containing therein a thermosetting resin and at least one lubricant selected from the group consisting of fatty acids and fatty acid ester.
    Type: Grant
    Filed: December 6, 1988
    Date of Patent: August 21, 1990
    Assignee: TDK Corporation
    Inventors: Hiroyuki Arioka, Masharu Nishimatsu, Toshiaki Ide
  • Patent number: 4947846
    Abstract: The present invention is characterized by a construction wherein a magnet is provided either to the connector or the ECG electrode, and a magnetic material or a magnet to the other, and both are stuck by magnetic attraction. Subsequently, a water penetration prevention sealing material, comprising a closed-cell type foam material, is interposed between the electrode case and the connector. Due to this construction, electric signals do not leak into the water and the connector is not pressed against the electrode.
    Type: Grant
    Filed: February 6, 1989
    Date of Patent: August 14, 1990
    Assignee: TDK Corporation
    Inventors: Toshiyuki Kitagawa, Namio Katoh
  • Patent number: 4949210
    Abstract: A tape cassette capable of ensuring firm joining between different resin layers of a casing and exhibiting a good aesthetic property. The tape cassette includes a casing consisting of upper casing member and lower casing member which are integrally made into a two-layer structure of a primary resin layer and a secondary resin layer integrally formed by two-layer molding. The secondary resin layer is formed with a plurality of penetrations and the primary resin layer is joined to the secondary resin layer in a manner to be fitted in the penetrations, resulting in being integral with the secondary resin layer.
    Type: Grant
    Filed: May 31, 1989
    Date of Patent: August 14, 1990
    Assignee: TDK Corporation
    Inventors: Takateru Satoh, Noboru Uemura, Haruo Shiba, Kimio Tanaka, Kenkichi Akaoka
  • Patent number: 4946729
    Abstract: A back coating resin composition for a magnetic recording medium comprising:(A) a plastic compound having a molecular weight of from 5,000 to 100,000 and containing at least two radiation-curable unsaturated double bonds;(B) a rubber-like compound having a molecular weight of from 3,000 to 100,000 and containing at least one radiation-curable unsaturated double bond or containing no such double bond; and(C) a compound having a molecular weight of from 200 to 3,000 and containing at least one radiation-curable unsaturated double bond.
    Type: Grant
    Filed: September 26, 1984
    Date of Patent: August 7, 1990
    Assignee: TDK Corporation
    Inventors: Masaharu Nishimatsu, Shigeru Shimada, Toshiaki Ide, Hiroyuki Arioka, Yuichi Kubota
  • Patent number: 4941818
    Abstract: The cigarette lighter of the invention has an igniter member which promotes smooth burning of the fuel gas ejected from the gas nozzle. The igniter member is composed of an igniting element which is a coiled wire of platinum metal or a platinum-based alloy having a specified dimensions and a supporting member made of a wire of a refractory metal or alloy. The coil of platinum wire preferably has a flattened configuration to cover a larger front of the flame. The supporting member made of a wire of a refractory metal or alloy, around which the coil is wound, is preferably coated with a coating layer of a ceramic material, e.g., alumina. A simple but very reliable structure for mounting the igniter member in the fire bowl of the cigarette lighter is described.
    Type: Grant
    Filed: November 18, 1988
    Date of Patent: July 17, 1990
    Assignee: TDK Corporation
    Inventors: Kazuhide Ohe, Kazuo Sato, Shunpei Fukuda, Hiroyuki Nakada
  • Patent number: 4939459
    Abstract: A magnetic sensor is provided for use in detecting an external magnetic field, typically geomagnetism. Pulse or alternating current is applied across a wire or strip-shaped electrically conductive, magnetic body in its longitudinal direction to create an internal magnetic field in the magnetic body. A pick-up winding is wound around the magnetic body. The sensor detects an electric signal developed in the winding as a result of interaction of the internal and external magnetic fields.
    Type: Grant
    Filed: December 21, 1988
    Date of Patent: July 3, 1990
    Assignee: TDK Corporation
    Inventors: Yoshiaki Akachi, Mutumi Kinosita
  • Patent number: 4939494
    Abstract: A surface-mounted-type inductance element comprising a coil structure having a bobbin; the bobbin including a portion around which wires are coiled, a pair of flanges integrally formed at opposing ends of the bobbin, a pair of bases integrally formed at lower edge portions of the flanges in a manner to project laterally from the flanges, and a plurality of external terminals attached to each of the bases in a manner to penetrate the base, each the external terminal including a first portion projecting laterally from the base and a second portion projecting downward from the base, around which first portion of each the external terminal a termination of any one of the wires is wound; a mold covering the coil structure in a manner to allow the second portions of the external terminals to be projected outward from the mold, the mold being formed of resin material exhibiting heat resistance; and a pair of cores assembled to the coil structure through the mold.
    Type: Grant
    Filed: April 24, 1989
    Date of Patent: July 3, 1990
    Assignee: TDK Corporation
    Inventors: Yoshiaki Masuda, Hiraku Imaizumi, Takashi Shioura, Tadashi Mitsui, Tokio Tadano
  • Patent number: 4939604
    Abstract: A magnetic head comprises a slider which holds recording/writing elements at its medium opposing surface constituting a lifting force generating part and the surface area of the medium opposing surface is at most 2 mm.sup.2.A magnetic recording and reproducing apparatus has such magnetic head which is disposed on a magnetic disk having a magnetic recording layer formed on a rigid substrate while the disk is rotated at a high speed so that magnetic recording and reproducing are conducted between the magnetic head and the magnetic disk, wherein the surface roughness R.sub.max of the magnetic disk is at most 100 .ANG..
    Type: Grant
    Filed: March 23, 1989
    Date of Patent: July 3, 1990
    Assignee: TDK Corporation
    Inventors: Kazumasa Fukuda, Masanori Sakai, Joichiro Ezaki, Mikio Matsuzaki
  • Patent number: RE33294
    Abstract: A casing for holding a magnetic tape cassette which is formed into a box shape by bending and joining a blank of a transparent .[.blastic.]. .Iadd.plastic .Iaddend.plate material which has one surface, constituting the inner surface of a casing, on which grooves and a minutely roughened area are provided except for on a predetermined portion including at least one transparent window and the other surface, constituting the outer surface of said casing, on which printing and/or an uneven surface pattern is provided in a predetermined portion except for said transparent window.
    Type: Grant
    Filed: April 19, 1989
    Date of Patent: August 14, 1990
    Assignee: TDK Corporation
    Inventors: Tatsuo Fujii, Shigetomo Takeda
  • Patent number: D311002
    Type: Grant
    Filed: August 26, 1987
    Date of Patent: October 2, 1990
    Assignee: TDK Corporation
    Inventors: Takateru Satoh, Masaru Ikebe, Kimio Tanaka