Patents Assigned to Murata Mfg. Co., Ltd.
  • Patent number: 6525625
    Abstract: A dielectric duplexer has first and second filters passing two adjacent bands and is not influenced by signals in bands that are outwardly adjacent to the two passing bands. The space between small sectional area portions on short-circuit-end sides of first and second resonator holes is arranged to be relatively small, and the two resonator holes are coupled with each other according to a distributed-constant-type inductive coupling method. The space between small sectional area portions on short-circuit-end sides of fourth and fifth resonator holes is arranged to be relatively large, and the two resonator holes are coupled with each other according to a distributed-constant-type capacitive coupling method. Furthermore, the space between small sectional area portions on short-circuit-end sides of the fifth resonator hole and a sixth resonator hole is arranged to be relatively small, and the two resonator holes are coupled with each other according to a distributed-constant-type inductive coupling method.
    Type: Grant
    Filed: July 28, 2000
    Date of Patent: February 25, 2003
    Assignee: Murata Mfg. Co. Ltd
    Inventors: Hideki Tsukamoto, Katsuhito Kuroda, Jinsei Ishihara, Hideyuki Kato
  • Publication number: 20020070819
    Abstract: A nonreciprocal circuit device and a communication apparatus using the same are provided. According to the nonreciprocal circuit device, without increasing the size of a housing for the nonreciprocal circuit device, a high-frequency component to be provided in the housing can be easily and securely mounted. Central conductors are arranged so as to mutually intersect; each of matching capacitors is connected to a portion between each of ports of the central conductors and each of ground terminals; and a nonreciprocal circuit is thereby configured. A resistor is premounted on a substrate. In this state, the substrate is installed in a resin housing.
    Type: Application
    Filed: November 30, 2000
    Publication date: June 13, 2002
    Applicant: Murata Mfg. Co., Ltd.
    Inventor: Takashi Hasegawa
  • Publication number: 20010019295
    Abstract: To provide a nonreciprocal circuit device which is compact and capable of obtaining a large attenuation in a specified frequency band without increasing the cost, and provided with at least a built-in inductor for a filter, a nonreciprocal circuit constituted together with the nonreciprocal circuit device, and a communication device using the circuit, central conductors are disposed in a ferrite to which the DC magnetic field is applied in an intersecting manner with each other, matching capacitors are respectively connected between port sections of the central conductors and a ground to constitute a nonreciprocal circuit, a solenoid-shaped inductor is connected between the port section of the central conductor and a signal input/output terminal, and the inductor is disposed in a relationship so that the direction of the magnetic flux which is generated by this inductor and passes through the ferrite is substantially perpendicular to the direction of the DC magnetic field to the ferrite.
    Type: Application
    Filed: November 30, 2000
    Publication date: September 6, 2001
    Applicant: Murata Mfg. Co., Ltd.
    Inventor: Takashi Hasegawa
  • Patent number: 6191667
    Abstract: A laminated body includes a first insulating sheet having first internal conductors disposed thereon, a second insulating sheet having second internal conductors are given, and a protective sheet, wherein the internal conductors define inductors. The first insulating sheet, the second insulating sheet and the protective sheet are stacked on top of each other and laminated to define the laminated body. When a distance between the end surfaces in a length direction of the laminated body and the inductors located adjacent the end surfaces is less than a fixed value, the internal conductors defining the inductors on the side of the end surfaces are arranged in a zig zag pattern which extends toward inner inductors.
    Type: Grant
    Filed: July 2, 1999
    Date of Patent: February 20, 2001
    Assignee: Murata Mfg. Co., Ltd.
    Inventors: Kazuhiko Takenaka, Tatsuru Takaoka
  • Patent number: 6164808
    Abstract: A three-dimensional data input device for a computer having a display screen includes a ball rotatably provided in a device body, and sensors for detecting rotation magnitudes of the ball along two axes on a plane and outputting displacement signals indicative of the detected rotation magnitudes, respectively. The device further includes a gyro for detecting an angular velocity of the device body about an axis extending at a given angle relative to the foregoing plane and outputting an angular velocity signal indicative of the detected angular velocity. The device further includes switches for outputting a selection signal in response to operation of at least one of selection buttons. The device derives displacement data based on the foregoing displacement signals and angular data based on the foregoing angular velocity signal and outputs the displacement data, the angular data and the selection signal to the computer.
    Type: Grant
    Filed: February 7, 1997
    Date of Patent: December 26, 2000
    Assignees: Murata MFG. Co., Ltd., Data Tec Co., Ltd.
    Inventors: Atsumi Shibata, Michiyasu Tano
  • Patent number: 5963590
    Abstract: A framing and voice decoder part outputs an error information. An error ratio monitoring part monitors a bit error ratio based on the error information. A sampling rate changing part decides a sampling rate based on the bit error ratio and changes a number of bits of each shift register in the differential detector part to adapt the sampling rate. A sampling clock selector part selects one clock signal among four different frequency clock signals based on the decision of the sampling rate changing part and gives selected clock signal to the differential detector part as a sampling clock. The differential detector part makes demodulation in DQPSK (Differential Quadrilateral Phase Shift Keying). Since the error ratio is always maintained within a predetermined extent, a good voice quality is obtained. Since the sampling rate will not increase to unnecessarily high levels, power saving can be achieved and a consumption of batteries is reduced.
    Type: Grant
    Filed: November 28, 1994
    Date of Patent: October 5, 1999
    Assignee: Murata Mfg. Co., Ltd.
    Inventors: Kazuyoshi Nakaya, Yoshiyuki Tabata
  • Patent number: 5956376
    Abstract: A framing and voice decoder part outputs an error information. An error ratio monitoring part monitors a bit error ratio based on the error information. A sampling rate changing part decides a sampling rate based on the bit error ratio and changes a number of bits of each shift register in the differential detector part to adapt the sampling rate. A sampling clock selector part selects one clock signal among four different frequency clock signals based on the decision of the sampling rate changing part and gives selected clock signal to the differential detector part as a sampling clock. The differential detector part makes demodulation in DQPSK (Differential Quadrilateral Phase Shift Keying). Since the error ratio is always maintained within a predetermined extent, a good voice quality is obtained. Since the sampling rate will not increase to unnecessarily high levels, power saving can be achieved and a consumption of batteries is reduced.
    Type: Grant
    Filed: December 30, 1996
    Date of Patent: September 21, 1999
    Assignee: Murata Mfg. Co., Ltd.
    Inventors: Kazuyoshi Nakaya, Yoshiyuki Tabata
  • Patent number: 5903240
    Abstract: A surface mounting antenna in which a wider frequency bandwidth can be achieved and a dual-frequency signal can be obtained without hampering the gain and needing to enlarge the configuration of the antenna. Also disclosed is a communication apparatus using this type of antenna. Two radiation electrodes for producing different resonant frequencies and a feeding electrode are formed on the obverse surface of a substrate formed of a dielectric material or a magnetic material. A ground electrode is primarily disposed on the reverse surface of the substrate. The radiation electrodes form open ends and are connected at the other ends to the ground electrode. The open ends of the radiation electrodes and the feeding electrode are electromagnetically coupled to each other through capacitances generated in gaps formed between the feeding electrode and the open ends.
    Type: Grant
    Filed: February 11, 1997
    Date of Patent: May 11, 1999
    Assignee: Murata Mfg. Co. Ltd
    Inventors: Kazunari Kawahata, Kazuhisa Yamaki
  • Patent number: 5874926
    Abstract: A matching circuit and an antenna apparatus which, though small-sized, can be used in a radio apparatus which transmits and receives radio waves having a wide range of frequencies. A matching circuit includes an inductance element formed of a chip inductor connected in series with an antenna body, a first capacitance element formed of a trimmer capacitor, and a second capacitance element formed of a chip capacitor, which capacitance elements are connected between respective ends of the inductance element and a ground terminal, and thus in parallel to the antenna body. One end of the inductance element is connected to the power supply terminal of the antenna body, and the other end is connected to a power source for applying a voltage to the antenna body. The first capacitance element is connected between a ground and the connection point of the power supply terminal of the antenna body and the inductance element.
    Type: Grant
    Filed: March 10, 1997
    Date of Patent: February 23, 1999
    Assignee: Murata Mfg Co. Ltd
    Inventors: Teruhisa Tsuru, Harufumi Mandai, Toshifumi Oida, Yoichiro Suga
  • Patent number: 5870065
    Abstract: A miniature chip antenna which can be utilized as an antenna for use in a high-frequency region is provided. The chip antenna comprises a substrate, at least one conductor, and at least one feeding terminal. The substrate comprises a dielectric material portion and a magnetic material portion, at least a part of the magnetic material portion being exposed to the exterior of the substrate. The conductor is formed at least either on the surface of the substrate or inside the substrate. The feeding terminal is provided on the surface of the substrate to impress a voltage on the conductor.
    Type: Grant
    Filed: October 8, 1996
    Date of Patent: February 9, 1999
    Assignee: Murata Mfg Co. Ltd.
    Inventors: Seiji Kanba, Teruhisa Tsuru, Kenji Asakura, Tsuyoshi Suesada, Harufumi Mandai
  • Patent number: 5870269
    Abstract: A demagnetizing circuit has a positive characteristic thermistor and a demagnetizing coil connected in series with an alternating current power supply and is so constructed that it is possible to suppress the production of a low-frequency electromagnetic field. After the completion of a demagnetizing operation, the demagnetizing coil and the alternating current power supply can be completely isolated from each other, i.e. both ends of the demagnetizing coil can be electrically cut off from the alternating current power supply, so that it is impossible for residual demagnetizing current from the alternating current power supply to produce a low-frequency electromagnetic field in the demagnetizing coil. Also, preferably, at least one end of the demagnetizing coil is kept at a reference potential by way of a capacitor to dissipate any currents which may be induced in the demagnetizing coil by any influence other than the alternating current power supply.
    Type: Grant
    Filed: April 19, 1996
    Date of Patent: February 9, 1999
    Assignee: Murata Mfg. Co., Ltd.
    Inventors: Yutaka Ikeda, Yuichi Takaoka, Kiyofumi Torii
  • Patent number: 5867126
    Abstract: A current-inducing-type surface-mount-type antenna which is short in length and thin in thickness and which can be formed into a small size and communication equipment having the same mounted therein. A radiation electrode substantially in the shape of a letter L or a sideways U and a power supply electrode are formed on the surface of a base made of a dielectric or a magnetic substance with a gap therebetween. A short-circuit end of the radiation electrode and the power supply electrode are connected to a grounding terminal and a power supply terminal, respectively, which are formed on an end surface of the base.
    Type: Grant
    Filed: February 12, 1997
    Date of Patent: February 2, 1999
    Assignee: Murata Mfg. Co. Ltd
    Inventors: Kazunari Kawahata, Ken Okada
  • Patent number: 5861854
    Abstract: A surface-mount antenna includes a radiation electrode formed on one or more surfaces of a rectangular parallelopiped base member comprising a dielectric or a magnetic substance so as to have one end as an open end and another end as a first ground electrode, a feeding electrode formed on the surface or surfaces, and a second ground electrode formed in proximity to the open end of said radiation electrode.
    Type: Grant
    Filed: June 13, 1997
    Date of Patent: January 19, 1999
    Assignee: Murata Mfg. Co. Ltd.
    Inventors: Kazunari Kawahata, Ken Okada
  • Patent number: 5861852
    Abstract: A downsized chip antenna having a large bandwidth ratio is disclosed. The chip antenna has a rectangular prism-shaped base member providing a mounting surface. A conductor is formed inside the base member in such a manner that it is spirally wound around a winding axis, for example, a winding axis parallel to the mounting surface, i.e., in the longitudinal direction of the base member. One end of the conductor is extended to a surface of the base member to form a feeding section, which is connected to a feeding terminal, disposed over the surfaces of the base member to apply voltage to the conductor. In one embodiment, the other end of the conductor is connected to a midway portion of the conductor within the base member, thereby forming a loop in said conductor.
    Type: Grant
    Filed: April 11, 1997
    Date of Patent: January 19, 1999
    Assignee: Murata Mfg. Co. Ltd.
    Inventors: Kenji Asakura, Teruhisa Tsuru, Seiji Kanba, Tsuyoshi Suesada
  • Patent number: 5850677
    Abstract: An opening is formed in a region of a circuit board opposite a vibration region E of a piezoelectric element. The piezoelectric element is mounted to the circuit board, and electrical connections extend between and support the piezoelectric element from the circuit board by a solder. The soldered connection portions are surrounded by a bonding agent. An opening in the circuit board prevents any excess bonding agent from invading the vibration region E of the piezoelectric element, and the bonding agent assists in dispersing stresses exerted on the circuit board thereby minimizing the stresses transferred to the piezoelectric element.
    Type: Grant
    Filed: November 14, 1996
    Date of Patent: December 22, 1998
    Assignee: Murata Mfg. Co., Ltd.
    Inventor: Morimoto Ryoichi
  • Patent number: 5840382
    Abstract: An electronic part having a plurality of substrates and a process for producing the same are disclosed, the electronic part comprising (1) a laminate comprising at least two previously fired substrates different in electrical characteristics each containing in the inside thereof a passive element, and an adhesive layer comprising glass which is interposed between said substrates, and (2) an outer electrode which is formed on the surface of the laminate of the substrates and is electrically connected to the passive elements, and the process comprising the steps of: separately firing at least two substrates different in electrical characteristics each containing in the inside thereof a passive element; adhering the substrates with an adhesive comprising glass; and forming an outer electrode on the surface of the laminate of the substrates in electrical connection to each passive element. Each substrate is free from warpage or cracking and containing no part remaining non-sintered.
    Type: Grant
    Filed: July 17, 1997
    Date of Patent: November 24, 1998
    Assignee: Murata Mfg. Co., Ltd.
    Inventors: Mitsuyoshi Nishide, Hiroji Tani
  • Patent number: 5818398
    Abstract: A surface mounting type antenna system 10 is formed by spirally winding a conductor 14 made of copper or copper alloy, with a power supply member 12 provided at one end of the conductor 14, the other end thereof being a free end 13, on the edge faces of a rectangular parallelepiped as a dielectric substrate 11 by printing, deposition, pasting or plating. The dielectric substrate 11 is prepared by stacking a plurality of layers of ceramics, resin or a combination of ceramics and resin. On the underside 111 of the dielectric substrate 11 lies a power supply terminal 15 to which the power supply member 12 of the conductor 14 is connected. The power supply terminal 15 is simultaneously used as a fixing terminal for securing the surface mounting type antenna system 10 to, for example, a mounting board. Moreover, the conductor 14 squarely intersecting the axis C of the conductor winding is rectangular in transverse cross section having a width of w and a length of l.
    Type: Grant
    Filed: March 25, 1997
    Date of Patent: October 6, 1998
    Assignee: Murata Mfg. Co., Ltd.
    Inventors: Teruhisa Tsuru, Haruhumi Mandai, Koji Shiroki, Kenji Asakura
  • Patent number: 5798737
    Abstract: A chip antenna having a substrate comprising either of a dielectric material or a magnetic material, at least one conductor formed on at least one side of a surface of the substrate or inside the substrate, and at least one feeding terminal provided on the surface of the substrate for applying a voltage to the conductor, a part of the conductor connecting with the feeding terminal. The end section of the conductor or a portion of the conductor other than an end section of the conductor may be connected with the feeding terminal.
    Type: Grant
    Filed: November 17, 1997
    Date of Patent: August 25, 1998
    Assignee: Murata Mfg. Co., Ltd.
    Inventors: Seiji Kanaba, Kenji Asakura, Tsuyoshi Suesada, Teruhisa Tsuru, Harufumi Mandai
  • Patent number: 5777587
    Abstract: An antenna includes a dielectric substrate, an input/output electrode, a metal wire, and a metal cap. The metal wire is coiled so that its forward end is connected to the input/output electrode through a connecting electrode and a lead electrode while its another end is connected to an inner surface of a top plate of the metal cap. The metal cap is fixed onto a major surface of the dielectric substrate.
    Type: Grant
    Filed: June 14, 1996
    Date of Patent: July 7, 1998
    Assignee: Murata Mfg. Co., Ltd.
    Inventors: Teruhisa Tsuru, Harufumi Mandai, Mitsuhide Kato
  • Patent number: 5731950
    Abstract: Disclosed is a monolithic ceramic capacitor comprising dielectric ceramic layers made from a ceramic composition, which comprises an essential component of (1-.alpha.-.beta.) {BaO}.sub.m .multidot.TiO.sub.2 +.alpha.{(1-x)M.sub.2 O.sub.3 +xRe.sub.2 O.sub.3 }+.beta.(Mn.sub.1-y-z Ni.sub.y Co.sub.z)O (0.0025.ltoreq..alpha..ltoreq.0.025; 0.0025.ltoreq..beta..ltoreq.0.05; .beta./.alpha..ltoreq.4; 0<x.ltoreq.0.50; 0.ltoreq.y<1.0; 0.ltoreq.z<1.0; 0.ltoreq.y+z<1.0; 1.000<m.ltoreq.1.035) and from 0.5 to mols, relative to 100 mols of the essential component, of a side component MgO, and contains from 0.2 to 3.0 parts by weight, relative to 100 parts by weight of said components, of an oxide of the type of Li.sub.2 O--(Si,Ti)O.sub.2 --Al.sub.2 O.sub.3 --ZrO.sub.2. The capacitor can be small-sized while having large capacity. It can be produced even through baking in atmospheres having a low oxygen partial pressure without producing semiconductors.
    Type: Grant
    Filed: December 18, 1996
    Date of Patent: March 24, 1998
    Assignee: Murata Mfg. Co. Ltd.
    Inventors: Norihiko Sakamoto, Harunobu Sano, Hiroyuki Wada, Yukio Hamaji