Patents Assigned to TDK Electronics Company, Limited
  • Patent number: 3995300
    Abstract: An improved reduction-reoxidation type semiconducting ceramic capacitor and the method for producing the same are disclosed. The main components of the substrate of the capacitor are CaTiO.sub.3, SrTiO.sub.3 and Bi.sub.2 O.sub.3.xTiO.sub.2. Said substrate also contains at least one member selected from the group consisting of manganese, cobalt, nickel, chromium, vanadium, niobium, tantalum, lanthanum and cerium ions in total amounts of 0.025 to 0.4% by weight. The capacitor according to the present invention excels, in the temperature independency of the capacitance and tan .delta., etc.
    Type: Grant
    Filed: August 14, 1974
    Date of Patent: November 30, 1976
    Assignee: TDK Electronics Company, Limited
    Inventors: Hitoshi Masumura, Shinobu Fujiwara, Hitoshi Tanaka
  • Patent number: 3990733
    Abstract: A hub for winding a magnetic tape thereon comprises a clamp for retaining one end of a magnetic tape. The novel tape clamp comprises a substantially rigid upper web, a resilient lower web and a pair of legs depending from the ends of the upper web and connected to the ends of the lower web. The lower web supplements the resilient force of the legs. As the upper web is not subjected to a stress, the magnetic tape is wound properly on the upper web.
    Type: Grant
    Filed: October 30, 1975
    Date of Patent: November 9, 1976
    Assignee: TDK Electronics Company, Limited
    Inventors: Haruo Shiba, Kimio Tanaka
  • Patent number: 3989042
    Abstract: In an oscillator-exciting system for a ultrasonic liquid nebulizer, a piezo-oscillator element for nebulizing the liquid is electrically connected to a self-exciting oscillating circuit as a constituent element thereof and the circuit is oscillated at that frequency at which the electric impedance of the piezo-oscillator element is inductive. A protective transistor may be connected to a current-bias resistance of the oscillating circuit, which protective transistor may be cut off by a reed switch sensing the exhaustion of the liquid being nebulized and/or by an overcurrent sensing circuit, for ceasing the oscillation in case of liquid exhaustion and/or overcurrent.
    Type: Grant
    Filed: May 29, 1975
    Date of Patent: November 2, 1976
    Assignee: TDK Electronics Company, Limited
    Inventors: Sadao Mitsui, Minoru Takahashi
  • Patent number: 3988816
    Abstract: An improved roller, consisting in part of a cylindrical permanent magnet, for use in electrostatic record developing devices is disclosed. Of the plurality of magnetic poles formed on the cylindrical surface of the permanent magnet, two of the same polarity are positioned with an auxiliary magnetic pole of opposite polarity located therebetween. The magnetic field intensity of the auxiliary magnetic pole is from about 1/10 to 1/2 that of the other magnetic poles.
    Type: Grant
    Filed: October 23, 1975
    Date of Patent: November 2, 1976
    Assignee: TDK Electronics Company, Limited
    Inventor: Takeo Tada
  • Patent number: 3977985
    Abstract: A magnetic recording medium is disclosed as comprising powdered magnetic particles upon which there is deposited a ferro-magnetic metal or alloy such as cobalt or a cobalt alloy. Each magnetic particle is a spiculate magnetite and the deposite of cobalt or a cobalt alloy is in the range of 0.5 wt.% to 30 wt.%. The particles are heat treated in either a reducing or inert atmosphere to a sufficient temperature to improve the magnetic characteristics of the particles including their coercive force, Br/.rho. and Bm/.rho.. A layer of the recording medium is disposed on a support layer of polyester to form a magnetic tape.
    Type: Grant
    Filed: December 13, 1974
    Date of Patent: August 31, 1976
    Assignee: TDK Electronics Company, Limited
    Inventors: Shinji Umeki, Fujio Shibata, Kazuo Takada
  • Patent number: 3958068
    Abstract: A process is disclosed for the production of powdered magnetic material for use in magnetic recording materials. The process comprises the steps of dispersing finely divided particles of a ferromagnetic oxide into an aqueous solution, dissolving therein salts of one or more ferromagnetic metals and a water soluble reducing agent, and then heating the dispersion while stirring to form and deposit a coating of the ferromagnetic metal (or alloy) on the surface of the finely divided particles of ferromagnetic oxide.
    Type: Grant
    Filed: May 30, 1972
    Date of Patent: May 18, 1976
    Assignee: TDK Electronics Company, Limited
    Inventors: Shinji Umeki, Fujio Shibata
  • Patent number: 3951873
    Abstract: A ceramic dielectric composition which comprises 22.5-45.2 wt. % SrO, 8.3-20.6 wt. % CaO, 29.3-80.8 wt. % TiO.sub.2, and 0.07-8.3 wt. % MgO as main components.
    Type: Grant
    Filed: August 2, 1974
    Date of Patent: April 20, 1976
    Assignee: TDK Electronics Company, Limited
    Inventors: Nobuaki Kikuchi, Tsunehiko Yoshioka, Kiyoshi Furukawa, Shinobu Fujiwara