Patents by Inventor Youhei Ishikawa

Youhei Ishikawa has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20040127313
    Abstract: During a downshift of a belt-drive continuously variable transmission, occurring owing to vehicle deceleration, a CVT controller foretells that a slippage between a drive belt and each of primary and secondary variable-width pulleys tends to occur, when a primary pulley pressure is less than a first predetermined pressure level and a primary pulley speed is less than a first predetermined rotational speed. When the belt slippage has been foretold, the CVT controller inhibits the primary pulley pressure from dropping by setting an actual transmission ratio calculated before a set time period from a time when the slippage has been foretold or a transmission ratio of a relatively higher speed side as compared with a ratio-change operating state obtained when the slippage has been foretold, to a desired transmission ratio, or by relatively rising a line pressure as compared with a line pressure level produced when the slippage has been foretold.
    Type: Application
    Filed: September 26, 2003
    Publication date: July 1, 2004
    Applicant: JATCO Ltd
    Inventors: Shigeki Shimanaka, Hiroyasu Tanaka, Youhei Ishikawa, Tatsuo Wakahara, Yoshihisa Kodama, Hideki Oshita
  • Patent number: 6362696
    Abstract: A device with a nonradiative dielectric waveguide which operates in a microwave band or in a millimeter wave band. The device with a nonradiative dielectric waveguide is, for example, an oscillator, a circulator, a coupler or the like. The device has a pair of parallel conductors, a dielectric strip which is disposed between the conductors and propagates a high-frequency electromagnetic wave in a specified mode, a mounting surface which is formed on one of the conductors, and an end surface which is defined by an end of each of the conductors so as to be vertical to a traveling direction of the electromagnetic wave propagated in the dielectric strip. An end of the dielectric strip is exposed at a corresponding end surface of the device.
    Type: Grant
    Filed: July 18, 2000
    Date of Patent: March 26, 2002
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Youhei Ishikawa, Toru Tanizaki, Hiroshi Nishida
  • Patent number: 6239757
    Abstract: A communication module for a vehicle including an automobile, a vessel or the like, the communication module being disposed on a back side or inside of an identification plate of the means of transportation. The communication module is formed of a millimeter wave integrated circuit section and a plane antenna section. The millimeter wave integrated circuit section has two conductive plates arranged in parallel with each other, and a dielectric stripline and an electric element disposed between the conductive plates. The plane antenna section has two conductive plates arranged in parallel with each other, a dielectric stripline disposed between the conductive plates and a slot made in one of the conductive plates. At least a respective one of the conductive plates of the millimeter wave integrated circuit section and a respective one of the conductive plates of the plane antenna section are integrated in a plane.
    Type: Grant
    Filed: April 22, 1997
    Date of Patent: May 29, 2001
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Youhei Ishikawa, Toru Tanizaki
  • Patent number: 6218916
    Abstract: A device with a nonradiative dielectric waveguide which operates in a microwave band or in a millimeter wave band. The device with a nonradiative dielectric waveguide is, for example, an oscillator, a circulator, a coupler or the like. The device has a pair of parallel conductors, a dielectric strip which is disposed between the conductors and propagates a high-frequency electromagnetic wave in a specified mode, a mounting surface which is formed on one of the conductors, and an end surface which is defined by an end of each of the conductors so as to be vertical to a traveling direction of the electromagnetic wave propagated in the dielectric strip. An end of the dielectric strip is exposed at a corresponding end surface of the device.
    Type: Grant
    Filed: February 20, 1998
    Date of Patent: April 17, 2001
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Youhei Ishikawa, Toru Tanizaki, Hiroshi Nishida
  • Patent number: 6148221
    Abstract: A plurality of TEM mode transmission lines (L2-L5) are structured by pairs of thin film conductors (21 and 22, 22 and 23, 23 and 24, and 24 and 25) which sandwich thin film dielectrics (31 to 34) by alternately stacking the thin film conductor (21 to 25) and the thin film dielectric (31 to 34). The phase velocities of TEM mode waves which are propagated at least by two of the transmission lines (L2 to L5) are substantially equal to each other. The thickness of each of the thin film conductors (21 to 25) is smaller than the skin depth of the frequency used so that the electromagnetic fields of at least two TEM mode transmission lines among the TEM mode transmission lines (L2 to L5) are coupled to each other. In this way, the skin depth can be increased effectively. The conductor loss and the surface resistance can be reduced significantly as compared to those of the conventional electrode. By use of this electrode, a transmission line, a resonator, a filter, and a high frequency device are structured.
    Type: Grant
    Filed: February 27, 1996
    Date of Patent: November 14, 2000
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Youhei Ishikawa, Seiji Hidaka
  • Patent number: 6008771
    Abstract: An antenna includes a cylindrically shaped dielectric resonator placed on a longitudinally extended axis of an elongated dielectric strip disposed on a planar conductor and another planar conductor having an opening covers the dielectric strip with the opening on the dielectric resonator. There may be another dielectric strip placed perpendicularly to the first dielectric strip such that the dielectric resonator is where the lines longitudinally extended from the axes of both dielectric strips will cross.
    Type: Grant
    Filed: September 8, 1997
    Date of Patent: December 28, 1999
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Nobuaki Tanaka, Kazunari Kawahata, Youhei Ishikawa, Seiichi Arai
  • Patent number: 5825268
    Abstract: A device with a nonradiative dielectric waveguide which operates in a microwave band or in a millimeter wave band. The device with a nonradiative dielectric waveguide is, for example, an oscillator, a circulator, a coupler or the like. The device has a couple of parallel conductors, a dielectric strip which is disposed between the conductors and propagates a high-frequency electromagnetic wave in a specified mode, a mounting surface which is formed on one of the conductors, and an end surface which is formed at an end of the conductors so as to be vertical to a traveling direction of the electromagnetic wave propagated in the dielectric strip. An end of the dielectric strip is exposed at a corresponding end surface of the device.
    Type: Grant
    Filed: August 27, 1996
    Date of Patent: October 20, 1998
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Youhei Ishikawa, Toru Tanizaki, Hiroshi Nishida
  • Patent number: 5757331
    Abstract: A leakage dielectric waveguide includes a housing made of plane-shaped electrical conductors located parallel to each other, and a dielectric strip for propagating a high-frequency wave between the parallel electrical conductors, wherein the dielectric strip is provided within the housing. The housing is arranged to be asymmetrical, thereby leaking and radiating a high-frequency wave propagating through the dielectric strip. The housing is preferably further composed of the plane-shaped parallel electrical conductors and a side wall. A plane antenna includes the above-mentioned leakage dielectric waveguide, and a projecting device for projecting the high-frequency wave toward a free space in response to a high-frequency wave being projected from the dielectric waveguide.
    Type: Grant
    Filed: January 11, 1996
    Date of Patent: May 26, 1998
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Tsukasa Yoneyama, Youhei Ishikawa, Tohru Tanizaki
  • Patent number: 5724013
    Abstract: A high-frequency integrated circuit which operates in a microwave band or in a millimeter wave band. The high-frequency integrated circuit has a plurality of devices with respective nonradiative dielectric waveguides such as an oscillator, a coupler, etc., and a substrate on which these devices are surface-mounted. Each of the devices has a pair of parallel conductors, a dielectric strip which is disposed between the conductors and propagates a high-frequency electromagnetic wave, a mounting surface which is formed on one of the conductors and is in contact with the substrate, and an end surface which is defined by an end of the conductors so as to be vertical to a traveling direction of the electromagnetic wave propagated in the dielectric strip and at which an end of the dielectric strip is exposed. The devices with a nonradiative dielectric waveguide are evaluated separately, and thereafter, the devices are surface-mounted on the substrate close to or in contact with one another.
    Type: Grant
    Filed: August 28, 1995
    Date of Patent: March 3, 1998
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Youhei Ishikawa, Toru Tanizaki, Hiroshi Nishida
  • Patent number: 5604469
    Abstract: A high-frequency integrated circuit which operates in a microwave band or in a millimeter wave band. The high-frequency integrated circuit has devices with a nonradiative dielectric waveguide such as an oscillator, a circulator, etc., and a mount case with a nonradiative dielectric waveguide in which these devices are mounted. Each of the devices with a nonradiative dielectric waveguide has a couple of conductors, a dielectric strip which is disposed between the conductors and propagates a high-frequency electromagnetic wave in a specified mode, a mounting surface which is formed on one of the conductors, and an end surface which is formed on an end of the conductors so as to be vertical to a traveling direction of the electromagnetic wave propagated in the dielectric strip and on which an end of the dielectric strip is exposed. The devices with a nonradiative dielectric waveguide are evaluated separately, and thereafter, the devices are mounted in the mount case individually.
    Type: Grant
    Filed: August 28, 1995
    Date of Patent: February 18, 1997
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Youhei Ishikawa, Toru Tanizaki, Hiroshi Nishida
  • Patent number: 5600289
    Abstract: A measuring jig which is used to measure characteristics of a device with a nonradiative dielectric waveguide which operates in a microwave band or in a millimeter wave band. The measuring jig has a mount section on which a device with a nonradiative dielectric waveguide is to be mounted, and a converting section which connects the device to an external circuit. The converting section has a couple of parallel conductors, a dielectric strip which is disposed between the conductors and propagates a high-frequency electromagnetic wave in a specified mode, and an end surface which is formed on an end of the conductors so as to be vertical to a traveling direction of the electromagnetic wave propagated in the dielectric strip and on which an end of the dielectric strip is exposed.
    Type: Grant
    Filed: August 28, 1995
    Date of Patent: February 4, 1997
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Youhei Ishikawa, Toru Tanizaki, Hiroshi Nishida, Norimitsu Tsukai, Atsushi Saito
  • Patent number: 5523725
    Abstract: A signal-to-noise enhancer 10 includes a first 90 degree hybrid set 20. A first output end of the first 90 degree hybrid set 20 is connected to an input end of a limiter used a magnetostatic wave element 62a utilized the magnetostatic surface wave mode. Also, a second output end of the first 90 degree hybrid set 20 is connected to an input end of a filter used a magnetostatic wave element 62b similar to the magnetostatic wave element 62a in structure, via a resistor 32 as a first attenuator. Furthermore, an output end of the limiter is connected to a first input end of a second 90 degree hybrid set 40 via a resistor 52 as a second attenuator. Also, an output end of the filter is connected to a second input end of the second 90 degree hybrid set 40.
    Type: Grant
    Filed: February 28, 1995
    Date of Patent: June 4, 1996
    Assignees: Murata Manufacturing Co., Ltd., Nippon Hoso Kyokai
    Inventors: Youhei Ishikawa, Takekazu Okada, Satoru Shinmura, Fumio Kanaya, Shinichiro Ichiguchi, Toshihito Umegaki, Toshihiro Nomoto
  • Patent number: 5473296
    Abstract: A nonradiative dielectric waveguide which includes a first housing and a second housing. The first housing and the second housing respectively include first and second dielectric units and conductor electrodes. The first and second dielectric units are respectively integrally formed with first and second planar portions, and first and second dielectric strip line portions extending outwardly from said first and second planar portions and by a predetermined height, with abutting faces generally parallel with the conductor electrodes and being provided at top portions of said dielectric strip line portions. The conductor electrodes are respectively formed in close contact with faces of the first and second dielectric units remote from the abutting faces. The first and second housings are overlapped so as to make the abutting faces confront each other. The first and second dielectric strip lines portions cooperate to propagate electromagnetic waves.
    Type: Grant
    Filed: March 3, 1994
    Date of Patent: December 5, 1995
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Youhei Ishikawa, Hiroshi Nishida, Atsushi Saito
  • Patent number: 5408690
    Abstract: In an antenna supervising apparatus for supplying a multiplexed signal comprised of a plurality of carrier wave signals respectively outputted from a plurality of transmitters through a transmission line to an antenna, a directional coupler detects progressive signals of the multiplexed signal to the antenna and the reflected signals thereof from the antenna, and a band-pass filter respectively filters the progressive signal and the reflected signal of one carrier wave signal preselected among those of the detected multiplexed signal. Further, a detector respectively detects the filtered progressive signal and the filtered reflected signal of the one carrier wave signal, and a micro processing unit calculates a standing wave ratio with respect to the preselected one carrier wave signal based on the detected signals.
    Type: Grant
    Filed: March 11, 1994
    Date of Patent: April 18, 1995
    Assignee: Murata Mfg. Co., Ltd.
    Inventors: Youhei Ishikawa, Sadao Yamashita, Hidekazu Wada
  • Patent number: 5379009
    Abstract: An active-type band pass filter achieves a compact structure and a minimum noise figure by setting a coupling Q factor (Q.sub.e1) on an input side of an amplifier, a coupling Q factor (Q.sub.e2) on an output side of the amplifier, and a gain G of the amplifier so that they satisfy the condition that Q.sub.e1 <Q.sub.e2 and 1/Q.sub.e1 =G/Q.sub.e2. By increasing the term with the negative symbol in the equation ##EQU1## the total no-load Q factor (Q.sub.o) is set in the negative region.
    Type: Grant
    Filed: July 15, 1993
    Date of Patent: January 3, 1995
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Youhei Ishikawa, Seiji Hidaka
  • Patent number: 5325077
    Abstract: A dielectric resonator apparatus is provided with a dielectric resonator which has a generally spherical dielectric placed within a shield case having a rectangular cavity, and uses each resonance of a x mode, a y mode and a z mode of TE.sub.101, where an electric field is caused respectively around a x axis, a y axis and a z axis of a rectangular coordinate system predetermined in the dielectric, and an external coupling means for coupling the above described resonator to an external circuit, whereby the dielectric resonator apparatus, which has no-load Q larger than in the conventional embodiment, can be made smaller in size, and also, can realize three resonators with one apparatus.
    Type: Grant
    Filed: August 28, 1992
    Date of Patent: June 28, 1994
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Youhei Ishikawa, Hidekazu Wada, Hiroshi Nishida, Seiji Hidaka
  • Patent number: 5291160
    Abstract: A filter apparatus in accordance with the present invention comprises, for example, a band-pass filter and a plurality of band-stop filters connected as the post-stage to the band-pass filter. The band-pass filter transmits a band containing a desired frequency band, and the band-stop filters attenuate undesirable frequency bands. Another filter apparatus in accordance with the present invention comprises, for example, a first band-pass filter, a circulator connected to the first band-pass filter, and second band-pass filters connected to the circulator. The first band-pass filter transmits a band containing a desired frequency band to the circulator, and the second band-pass filters transmit undesirable frequency bands and reflect the desired frequency band back to the circulator. The desired frequency band is outputted from this circulator. Still another filter apparatus in accordance with the present invention comprises, for example, a circulator and a band-pass filter connected to the circulator.
    Type: Grant
    Filed: March 6, 1992
    Date of Patent: March 1, 1994
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Youhei Ishikawa, Jun Hattori, Toshio Nishikawa
  • Patent number: 5235294
    Abstract: An auto-tuned apparatus for a band-pass filter, wherein, the generated reference signals having the given frequency to be set are mixed with signals to be outputted from the band-pass filter when the reference signals have been inputted to the band-pass filter so as to multiply them for outputting the signals of the multiplied results, the signals of the direct current component from the signals of the multiplied results to be outputted are filtered, and the band-pass filter is controlled so that the center frequencies of the band-pass filter may agree with the frequencies of the reference signal in accordance with the signal of the direct current component to be outputted, whereby the center frequency of the band-pass filter can be adjusted automatically to the desired set value with simple circuit construction and precision better than in the conventional embodiment.
    Type: Grant
    Filed: January 17, 1992
    Date of Patent: August 10, 1993
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Youhei Ishikawa, Hidekazu Wada, Sadao Yamashita, Hiroyuki Kubo
  • Patent number: 5229729
    Abstract: A radio frequency signal combining/sorting apparatus which includes a plurality of channel filters which allow band regions of respective transmission channels to pass through them, isolators connected to respective inputs of the channel filters, a plurality of sets of power composing circuits each including branch lines for composing outputs of the channel filters into one output, and hybrid circuits arranged to each compose the outputs per two sets of the power composing circuits. The band regions to be applied to the respective channel filters are selected in such relation that the band regions of the respective channel filters corresponding to a given power composing circuit are spaced from each other to the largest possible extent.
    Type: Grant
    Filed: July 13, 1992
    Date of Patent: July 20, 1993
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Toshio Nishikawa, Youhei Ishikawa, Koichi Takehara
  • Patent number: 5184096
    Abstract: A parallel connection multi-stage band-pass filter including an input terminal and an output terminal for signals, a plurality of resonators respectively having resonator frequencies different from and close to one another which are electrically connected in parallel to each other between said input and output terminals.
    Type: Grant
    Filed: August 27, 1991
    Date of Patent: February 2, 1993
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Kikuo Wakino, Toshio Hishikawa, Youhei Ishikawa, Koichi Takehara, Toru Tanizaki