Patents Assigned to TDK Electronics Co. Ltd.
  • Patent number: 4346537
    Abstract: A capacitor trimming system for a quartz-crystal oscillator in a watch and/or a clock for providing a punctual watch and/or a clock has been found. The system comprises an oscillation circuit including at least a quartz-crystal piece, a trimmer capacitor for adjusting the oscillating frequency of the quartz-crystal piece, a semiconductor electronic circuit for operating said quartz-crystal piece, and apparatus for adjusting automatically the trimmer capacitor so that the oscillating frequency becomes the same as the desired reference frequency. The trimmer capacitor comprises of at least a fixed outer trimming electrode, an inner common electrode fixed parallel to said trimming electrode and a dielectric body sandwiched between the two electrodes.
    Type: Grant
    Filed: November 27, 1979
    Date of Patent: August 31, 1982
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Sho Masujima, Shoichi Iwaya
  • Patent number: 4343834
    Abstract: A magnetic recording medium is prepared by a tilt vapor deposition of magnetic particles from a vapor thereof on a substrate running along a peripheral surface of a cylindrical can in vacuum wherein plural cans are used to deposit said magnetic particles at substantially the same tilt angle on each of said cans.
    Type: Grant
    Filed: March 26, 1981
    Date of Patent: August 10, 1982
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Seitoku Saito, Toshiaki Izumi, Hiroshi Sugihara, Takayoshi Kobuke, Kazuo Takada
  • Patent number: 4341358
    Abstract: A hub for magnetic tape having a recess formed in the peripheral part of the hub and a magnetic-tape clamp to be fitted into the recess comprises an upper rib having an outer surface with the same curvature as that of the hub; legs formed at both ends of the upper rib; projections extending outward from the legs to be fitted into the side wall grooves of the recess; and lower ribs extending inward from the legs to terminate in the vicinity of a convex portion formed in the central part of the recess bottom.
    Type: Grant
    Filed: September 26, 1980
    Date of Patent: July 27, 1982
    Assignee: TDK Electronics Co., Ltd.
    Inventor: Shigemasa Shoji
  • Patent number: 4340644
    Abstract: A magnetic recording medium consisting of a base coated with magnetic coating material which is a dispersion of magnetic particles using a vinyl chloride-vinyl acetate copolymer and a polyester resin as binder, characterized by the addition of a vinyl chloride-vinyl acetate copolymer containing at least 10% of vinyl alcohol. The use of the last-mentioned copolymer improves the frequency response characteristic as well as the mechanical properties such as the running quality.
    Type: Grant
    Filed: November 19, 1979
    Date of Patent: July 20, 1982
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Hiroshi Ota, Eiji Horigome, Hitoshi Azegami
  • Patent number: 4340506
    Abstract: A photoelectric transfer device in which an electroconductive layer is formed on a surface of an oxide substrate comprising lead component at a ratio of 30-99.5 mol % as PbO and chromium component at a ratio of 0.5-70 mol %, preferably at a ratio of 60-90 mol % as PbO and a chromium component at a ratio of 10-40 mol %.
    Type: Grant
    Filed: July 26, 1979
    Date of Patent: July 20, 1982
    Assignees: TDK Electronics Co., Ltd., Kohji Toda
    Inventors: Kohji Toda, Koji Takahashi, Isao Matsufuji
  • Patent number: 4339425
    Abstract: Acicular hydrated ferric oxide particles are produced by premixing an aged ferric hydroxide with a newly formed ferric hydroxide or a mixture of ferrous hydroxide and an oxidizing agent and treating the pre-mixture by a hydrothermal reaction of said pre-mixture at 100.degree. to 250.degree. C.
    Type: Grant
    Filed: November 25, 1980
    Date of Patent: July 13, 1982
    Assignee: TDK Electronics Co., Ltd.
    Inventor: Yasumichi Tokuoka
  • Patent number: 4338510
    Abstract: An electrode type steam vaporizer device is disclosed which includes a plurality of ferrite electrodes positioned in a water receptacle wherein AC voltage is applied to the electrodes thereby vaporizing water in the receptacle. Each of the ferrite electrodes is a sintered body made of a mixture of iron oxide and a divalent nickel oxide. The ferrite electrodes are contained in an electrode assembly located within the body of the water receptacle such that a pair of electrode terminals extend through the top wall of the receptacle. A cover having a power source connector receiving concavity in its surface is positioned on top on the water receptacle. The cover is rotatable between a first position where the concavity is in registry with the electrode terminals and a second position where the concavity is out of registry with the terminals. A power source connector is received in the concavity and is connectable with the electrode terminals only when the cover is in the first position.
    Type: Grant
    Filed: February 17, 1978
    Date of Patent: July 6, 1982
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Masao Chihara, Shigeo Araki, Kazuhiko Asakawa
  • Patent number: 4338576
    Abstract: Noise potentials and radiation in an ultrasonic nebulizer are reduced by separating the oscillator and power supply and shielding the former, with one of the DC power lines to the oscillator passing through an aperture in the metal casing that shields the oscillator, while the other power supply line is connected to that casing. Oscillator control may be achieved by an unshielded variable resistor coupled by conductors of extended length to the oscillator by a filter circuit.
    Type: Grant
    Filed: July 3, 1979
    Date of Patent: July 6, 1982
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Minoru Takahashi, Sadao Mitsui
  • Patent number: 4338367
    Abstract: A magnetic recording tape comprises a polyethyleneterephthalate base film coated with a magnetic layer which has an index H given by the equation:1.5>19.00-0.406 d.sub.B -0.016 H-0.553 d.sub.Td.sub.T .ltoreq.18(.mu.m)wherein the reference d.sub.T (.mu.m) designates a total thickness of the magnetic recording tape; d.sub.B (.mu.m) designates a thickness of the base film and H designates a sum of numbers of interference rings (H.sub.1, H.sub.2, H.sub.3 . . . )per 1 mm.sup.2.
    Type: Grant
    Filed: September 15, 1980
    Date of Patent: July 6, 1982
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Yoshio Kawakami, Yoneo Matsuzawa, Norifumi Kajimoto
  • Patent number: 4336310
    Abstract: A magnetic recording medium comprises a substrate coated with a magnetic layer comprising a binder resin and a metallic magnetic powder supporting silica on the surface which is coated with sequential layers of hydrolyzed silane compound and oleic acid. A magnetic recording medium is produced by sequentially treating a metallic magnetic powder supporting silica on the surface with a solution of a hydrolyzable silane compound and a solution of oleic acid to obtain a magnetic powder having the coated sequential layers and admixing the coated magnetic powder with a binder resin to prepare a magnetic composition and coating the magnetic composition on a substrate to form a magnetic layer.
    Type: Grant
    Filed: November 19, 1980
    Date of Patent: June 22, 1982
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Kiyotaka Okuyama, Akihiko Hosaka, Yukihiro Isobe
  • Patent number: 4335291
    Abstract: A popped corn making apparatus used in a microwave oven comprises a bowl having an opening at the upper part and a narrow closed bottom and a substantially conical shape; and a resonator placed at the bottom of said bowl. The electric field resulted by resonance of said resonator under an application of microwave, is applied to grains of corn contained in said bowl to produce a popped corn.It is possible to use a lumped element resonator comprising a one turn coil having a ring shape having an opening which is placed at the bottom of said bowl and which is formed by an inductance provided by said coil and a capacitance provided by said bowl and said grains of corn.
    Type: Grant
    Filed: April 4, 1980
    Date of Patent: June 15, 1982
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Ken Ishino, Taro Miura, Yasuo Hashimoto
  • Patent number: 4333620
    Abstract: A tape cassette including a pair of plates having a pair of bent portions each for holding magnetic tape and reel hubs on which the magnetic tape is wound. A plurality of cut portion are formed in each of the bent portions for defining portions facing the reel hubs, such portions projecting toward the reel hubs so as to be in contact with the reel hubs.
    Type: Grant
    Filed: March 19, 1980
    Date of Patent: June 8, 1982
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Toshihiko Ishida, Kimio Tanaka
  • Patent number: 4332863
    Abstract: A magnetic recording medium comprises a substrate coated with a binder and a magnetic powder obtained by forming an oleic acid layer on a surface of a metal or alloy magnetic powder obtained by a dry reduction.
    Type: Grant
    Filed: August 5, 1980
    Date of Patent: June 1, 1982
    Assignee: TDK Electronics Co., Ltd.
    Inventor: Akihiko Hosaka
  • Patent number: 4331489
    Abstract: A magnetic powder is produced by mixing an aqueous solution of a metal salt with an aqueous solution of a reducing agent such as sodium boron hydride in a magnetic field to reduce said metal salt to continuously form a magnetic powder and heat-treating said magnetic powder in a non-oxidative atmosphere. The aqueous solution of a metal salt is mixed with said aqueous solution of a reducing agent in a magnetic field to continuously discharge a reaction mixture containing a magnetic powder having pH of 2.5 or lower from a reactor and said reaction mixture containing said magnetic powder is immediately continuously washed and filtered and said magnetic powder is heat-treated in said non-oxidative atmosphere.
    Type: Grant
    Filed: November 6, 1980
    Date of Patent: May 25, 1982
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Tatsuo Uehori, Akio Watanabe, Tosiaki Ide
  • Patent number: 4330068
    Abstract: A three-piece structure magnetic tape cassette comprises an upper plate, an intermediate frame and a lower plate wherein annular bosses having counter-sunk holes are formed in the upper plate and annular bosses having threaded portions are formed in the lower plate and a seat portion is formed at the intermediate portion in clearance holes of the intermediate frame so that the ends of the annular bosses are brought into contact with the seat portion when the annular bosses are inserted into the clearance holes, and the upper plate, the intermediate frame and the lower plate are connected together with tapping screws.
    Type: Grant
    Filed: June 25, 1980
    Date of Patent: May 18, 1982
    Assignee: TDK Electronics Co., Ltd.
    Inventor: Shigemasa Shoji
  • Patent number: 4329398
    Abstract: A magnetic recording medium consisting of a base coated with a magnetic coating material, characterized in that the binder composition in said magnetic coating material is ternary, consisting of from 30 to 70% of a polyurethane resin having an --OH group in the terminal position, from 10 to 50% of an epoxy resin, and from 10 to 50% of a vinyl chloride-vinylidene chloride copolymer, all by weight on the basis of the total weight of the binder together with a curing agent. The magnetic recording medium exhibits superior electromagnetic properties and physical properties such as stability on repeated runs and bonding strength of the coating.
    Type: Grant
    Filed: November 19, 1979
    Date of Patent: May 11, 1982
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Akihiko Hosaka, Kazushi Tanaka
  • Patent number: 4328458
    Abstract: A variable leakage transformer having a closed main magnetic path and a closed submagnetic path having a leg common with said main magnetic path. A primary winding is wound on said common leg, and a secondary winding is wound on said main magnetic path. The magnetic flux in the common leg is controlled by other control windings which are connected to a control DC power source. The primary winding has two portions, and one of them is closely coupled magnetically with the secondary winding in order to improve the output waveform. By controlling the magnetic flux in the sub-magnetic path, the leakage of the flux induced by the primary winding from the main magnetic path to the sub-magnetic path can be controlled; thus the coupling between the primary and the secondary winding, and conduction period in each cycle of the AC output voltage are controlled. The control of the conduction period in each cycle provides control of the power transmitted from the primary winding to the secondary winding.
    Type: Grant
    Filed: December 4, 1979
    Date of Patent: May 4, 1982
    Assignee: TDK Electronics Co., Ltd.
    Inventor: Hirayama Hiromitsu
  • Patent number: 4327346
    Abstract: In an anisotropic polymeric magnet in tubular form, the magnetization orientation is directed in one direction perpendicular to the axial line of the tubular magnet. In a bipolar anisotropic magnet in tubular form, the magnetic poles can be formed only at symmetrical portions of the magnet with respect to the axial line and an imaginary line connecting the magnetic poles with each other is parallel to said one direction.In order to symmetrically distribute the magnetism around a tubular bipolar anisotropic magnet, a weld line(s) formed by injection molding of a mixture of ferromagnetic material powder and polymeric material is located in the portion(s) of the magnet where the magnetic poles are not formed.
    Type: Grant
    Filed: February 14, 1980
    Date of Patent: April 27, 1982
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Takeo Tada, Katsuji Honda, Yoshifumi Hirata
  • Patent number: 4327348
    Abstract: A variable leakage transformer or a variable voltage transformer comprising a magnetic core with a main-magnetic path and a sub-magnetic path, the main magnetic path having at least a common magnetic path with the submagnetic path, a primary winding wound on said common magnetic path of the core, a secondary winding wound on said main magnetic path of the core, means for controlling the magnetic flux in said sub-magnetic path, and said main-magnetic path having a thin air gap. By controlling the magnetic flux in the sub-magnetic path, the leakage of the flux induced by the primary winding from the main-magnetic path to the sub-magnetic path can be controlled. Thus the coupling between the primary and secondary windings, and conduction period in each cycle of the AC output voltage are controlled. The control of the conduction period in each cycle provides the control of the power transmitted from the primary winding to the secondary winding.
    Type: Grant
    Filed: October 3, 1979
    Date of Patent: April 27, 1982
    Assignee: TDK Electronics Co., Ltd.
    Inventor: Hiromitsu Hirayama
  • Patent number: D264959
    Type: Grant
    Filed: June 22, 1979
    Date of Patent: June 15, 1982
    Assignee: TDK Electronics Co. Ltd.
    Inventors: Junpei Ota, Masaru Wasaki, Tadashi Mitsui