Patents by Inventor Keiichi Iiyama

Keiichi Iiyama 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).

  • Patent number: 6894885
    Abstract: The reader/writer of this invention includes a high voltage withstanding amplifier, plural resonance circuits and plural high voltage withstanding analog switching circuits. The high voltage withstanding amplifier amplifies an analog signal to be sent to the outside. Each of the resonance circuits sends the analog signal amplified by the high voltage withstanding amplifier to the outside. The high voltage withstanding analog switching circuits are provided between the high voltage withstanding amplifier and the resonance circuits correspondingly to the resonance circuits. Each of the high voltage withstanding analog switching circuits electrically connects/disconnects the high voltage withstanding amplifier to/from the corresponding resonance circuit. Since the reader/writer includes the high voltage withstanding analog switching circuits, there is no need to provide high voltage withstanding amplifiers at the previous stages of the resonance circuits as in a conventional reader/writer.
    Type: Grant
    Filed: January 22, 2002
    Date of Patent: May 17, 2005
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Nobuyoshi Asaka, Keiichi Iiyama
  • Patent number: 6772953
    Abstract: An electronic circuit module formed of an antenna coil and an integrated circuit provided on a circuit board is provided inside a hollow resin case formed of a first part and a second part. A first slit leading into the hollow portion is provided in one side face of the resin case formed of the first and second parts joined to each other. Since the electronic circuit module is not exposed to high temperatures and high pressure during the manufacturing process, defects such as the breakage of the integrated circuit or the disconnection of the antenna coil can be avoided. Since the slit leading into the hollow portion is provided, the hollow portion does not swell by the temperature increase. In addition, pinholes do not tend to be formed during the joining of the first and second parts. Thus, a contactless data carrier with an excellent electrostatic withstand voltage characteristic can be provided.
    Type: Grant
    Filed: February 1, 2001
    Date of Patent: August 10, 2004
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Keiichi Iiyama, Takashi Noda, Shinji Murakami, Yutaka Harada, Takuya Oka, Masaru Tanichi
  • Patent number: 6489883
    Abstract: A non-contact data carrier includes a battery, an electric-supply circuit for rectifying a received carrier signal and generating power, and an electric-supply switching circuit for comparing the voltage of the battery and the voltage generated by the electric-supply circuit and selecting either one of the voltages. When the battery can supply power, long-distance communication can be performed by supplying power from the battery. In case of battery exhaustion, power is supplied from the electric-supply circuit which receives a stronger carrier signal by using the non-contact IC card in the proximity of a question unit and rectifies the carrier signal, so that the function of the non-contact data carrier is maintained.
    Type: Grant
    Filed: April 27, 1998
    Date of Patent: December 3, 2002
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Keiichi Iiyama, Nobuyoshi Asaka
  • Publication number: 20020121814
    Abstract: The reader/writer of this invention includes a high voltage withstanding amplifier, plural resonance circuits and plural high voltage withstanding analog switching circuits. The high voltage withstanding amplifier amplifies an analog signal to be sent to the outside. Each of the resonance circuits sends the analog signal amplified by the high voltage withstanding amplifier to the outside. The high voltage withstanding analog switching circuits are provided between the high voltage withstanding amplifier and the resonance circuits correspondingly to the resonance circuits. Each of the high voltage withstanding analog switching circuits electrically connects/disconnects the high voltage withstanding amplifier to/from the corresponding resonance circuit. Since the reader/writer includes the high voltage withstanding analog switching circuits, there is no need to provide high voltage withstanding amplifiers at the previous stages of the resonance circuits as in a conventional reader/writer.
    Type: Application
    Filed: January 22, 2002
    Publication date: September 5, 2002
    Inventors: Nobuyoshi Asaka, Keiichi Iiyama
  • Publication number: 20020017569
    Abstract: An electronic circuit module formed of an antenna coil and an integrated circuit provided on a circuit board is provided inside a hollow resin case formed of a first part and a second part. A first slit leading into the hollow portion is provided in one side face of the resin case formed of the first and second parts joined to each other. Since the electronic circuit module is not exposed to high temperatures and high pressure during the manufacturing process, defects such as the breakage of the integrated circuit or the disconnection of the antenna coil can be avoided. Since the slit leading into the hollow portion is provided, the hollow portion does not swell by the temperature increase. In addition, pinholes do not tend to be formed during the joining of the first and second parts. Thus, a contactless data carrier with an excellent electrostatic withstand voltage characteristic can be provided.
    Type: Application
    Filed: February 1, 2001
    Publication date: February 14, 2002
    Inventors: Keiichi Iiyama, Takashi Noda, Shinji Murakami, Yutaka Harada, Takuya Oka, Masaru Tanichi
  • Patent number: 6215272
    Abstract: A fuel cell device, wherein, after an output voltage from a main body of a fuel cell is converted using a converter, the relation between the resultant predetermined output voltage V 1 and an output voltage V 2 from a secondary battery is so set as to satisfy V 1>V 2. When, at the time of a sudden change of an external load, the output voltage V from the main body of the fuel cell becomes lower than a predetermined voltage V 3, an output to a charge controlling unit is stopped. When the output voltage V from the main body of the fuel cell is lowered even further and becomes lower than a predetermined voltage V 4, an output to an auxiliary device, which is necessary for driving the fuel cell device, is switched from the output from the converter to the output from the secondary battery.
    Type: Grant
    Filed: December 9, 1999
    Date of Patent: April 10, 2001
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hideo Ohara, Makoto Uchida, Yuko Fukuoka, Yasushi Sugawara, Nobuo Eda, Keiichi Iiyama
  • Patent number: 5949826
    Abstract: A data transmission and reception system according to this invention comprises a transmitter for transmitting data by modulating transmit data and a receiver for receiving and demodulating a signal from the receiver, wherein the receiver includes a parallel resonator for receiving a PSK signal; a full rectification circuit for detecting output from the parallel resonator; a low pass filter for shaping the waveform of output from the full rectification circuit; and a comparator for converting output from the low pass filter into a binary-coded signal so that demodulated signals can be obtained from the output of the comparator.
    Type: Grant
    Filed: December 19, 1996
    Date of Patent: September 7, 1999
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Keiichi Iiyama, Itsuo Takamiya, Masayuki Arai, Akihisa Yamazaki, Seiki Yokozeki