Patents by Inventor Singo Ichikawa

Singo Ichikawa 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: 4780841
    Abstract: A method and apparatus processes data representing measured values which are liable to show a poor consistency. Measured values are formed in groups; an average value and a discreteness value of a first group of measured values are calculated; an average value is presented as a most appropriate value to a display only when the discreteness value is below a reference value; otherwise, an average value and a discreteness value of the first and additional groups of measured values are calculated, and the recalculation is continued until the discreteness value has come to be below a reference value which decreases with the number of additional groups of measured values of which an average value and a discreteness value are calculated. The average value is presented as a most appropriate value to a display when the discreteness value is below the reference value.
    Type: Grant
    Filed: October 18, 1985
    Date of Patent: October 25, 1988
    Assignee: Citizen Watch Co.
    Inventors: Singo Ichikawa, Yasuo Kamiyama
  • Patent number: 4451743
    Abstract: A DC-to-DC voltage converter is disclosed for converting the voltage from a battery to provide a power supply voltage whose value can be equal to the battery voltage multiplied by or divided by a non-integral factor, e.g. 2/3. The converter operates on the principle of capacitor charge switching, and high conversion efficiency is achieved in operation at very low levels of supply current, such as are utilized in an electronic timepiece.
    Type: Grant
    Filed: December 9, 1981
    Date of Patent: May 29, 1984
    Assignee: Citizen Watch Company Limited
    Inventors: Fuminori Suzuki, Singo Ichikawa
  • Patent number: 4282594
    Abstract: An electronic timepiece is equipped with a frequency division ratio adjustment circuit controlled by switch means, for producing a running rate correction signal that is aperiodically added in frequency to the output of a standard frequency oscillator, to correct the running rate of the timepiece, and is provided with externally controlled gate means for inhibiting this aperiodic frequency addition, so that the actual frequency of the standard frequency oscillator may be measured by means such as an external monitoring device which detects a display drive or modulation signal frequency through electrostatic or electromagnetic coupling to the timepiece display.
    Type: Grant
    Filed: December 3, 1979
    Date of Patent: August 4, 1981
    Assignee: Citizen Watch Company Limited
    Inventor: Singo Ichikawa
  • Patent number: 4272838
    Abstract: An electronic watch module structure adapted to be disposed and supported by a case body of the watch. The module structure comprises a plastic base which has a first axial recess formed on one side of the plastic base, a second axial recess formed on the other side of the plastic base, a circuit board disposed in the first axial recess, an electro-optical display cell disposed on one side of the circuit board, and retaining means for retaining the display cell in a fixed place relative to the circuit board.
    Type: Grant
    Filed: March 20, 1979
    Date of Patent: June 9, 1981
    Assignee: Citizen Watch Co., Ltd.
    Inventors: Noriyuki Kasama, Singo Ichikawa
  • Patent number: 4270193
    Abstract: An electronic timepiece adapted to perform time correction in response to a train of time correction pulses transmitted from another electronic timepiece. The electronic timepiece comprises a detecting means to detect the train of time correction pulses; a writing-in signal generator circuit to generate writing-in signals in synchronism with a synchronizing signal contained in the train of time correction pulses, and a writing-in gate circuit means to perform writing-in of the train of time correction pulses into a timekeeping circuit of the timepiece as new current time data in response to the writing-in signals.
    Type: Grant
    Filed: April 2, 1979
    Date of Patent: May 26, 1981
    Assignee: Citizen Watch Company Limited
    Inventor: Singo Ichikawa
  • Patent number: 4268913
    Abstract: An electronic calculator watch which comprises timekeeping means composed of an oscillator, a frequency divider connected to the oscillator, a counter circuit connected to the frequency divider, and a driver circuit connected to the counter circuit for providing an output signal indicative of time information, and calculating means composed of an oscillator circuit and a calculation circuit responsive to perform calculations under control of numerical inputs furnished by external operation device provided on a watch case. The watch also comprises a display including a first display section connected to the driver circuit of the timekeeping means to display the output signal delivered therefrom, and a second display section connected to the calculating means to display the result of calculations, each of the first and second display sections having a plurality of digit electrodes and a plurality of segment electrodes arranged in a matrix configuration.
    Type: Grant
    Filed: May 13, 1977
    Date of Patent: May 19, 1981
    Assignee: Citizen Watch Co., Ltd.
    Inventors: Tadahiko Nakagiri, Kunihiro Daigo, Toshiaki Oguchi, Minoru Natori, Toshikazu Hatuse, Toshikazu Shimazaki, Kouhei Kawanobe, Hiroshi Ogawa, Yoshinobu Kashima, Singo Ichikawa, Ryo Namiki, Hisao Yamagata
  • Patent number: 4261048
    Abstract: An analog quartz timepiece having a manually operated external control member, and a correction signal generation circuit controlled by the external control member to generate low speed and high speed correction signals when the external control member is actuated for a short period of time and for a predetermined time interval, respectively, by which a stepping motor is driven at a selected speed to perform time correction. The timepiece also includes a click mechanism operative to shift an hours hand step-wise from any optional position without affecting a minutes hand and a seconds hand. The timepiece further includes a seconds zero-reset mechanism operative to reset the seconds hand to zero.
    Type: Grant
    Filed: June 8, 1979
    Date of Patent: April 7, 1981
    Assignee: Citizen Watch Company Limited
    Inventors: Jinro Motoki, Singo Ichikawa, Kenzi Miyasaka, Hiroyuki Uematsu, Mitsuhiro Murata, Hideyuki Kawashima, Yuri Inoue, Masae Ohkubo, Mituo Oooka
  • Patent number: 4236237
    Abstract: In an electronic wristwatch having a digital type of photo-electric display and powered by a battery, a battery life warning system is provided whereby the battery voltage is checked at periodic intervals and the photoelectric display is caused to flash on and off repetitively to indicate the approach of the end of the battery life. The timing of sampling pulses applied to a voltage detection circuit is controlled such that a temporary drop in battery voltage does not cause a display warning signal to be generated.
    Type: Grant
    Filed: July 28, 1978
    Date of Patent: November 25, 1980
    Assignee: Citizen Watch Company Limited
    Inventor: Singo Ichikawa
  • Patent number: 4232512
    Abstract: A solid state watch module construction including a plastic substrate and an electro-optical display cell directly mounted on the substrate. The substrate has an integrated circuit chip on one side thereof, and a plurality of printed circuit leads connected to electrical terminals of the integrated circuit chip. The electro-optical display cell has a plurality of electric terminals formed in rows in alignment with terminal ends of said printed circuit leads. The electro-optical display cell is bonded to the one side of the substrate and the electric terminals of the display cell are bonded to the terminal ends of the printed circuit leads.
    Type: Grant
    Filed: December 22, 1977
    Date of Patent: November 11, 1980
    Assignee: Citizen Watch Co., Ltd.
    Inventors: Kenichi Yoshikawa, Makoto Koshikawa, Toshio Umemoto, Tetsuo Satoh, Singo Ichikawa, Yoshiaki Kato
  • Patent number: 4226081
    Abstract: An electronic timepiece which makes use of a lithium battery having a high electric power capacity is disclosed. The timepiece comprises in combination a voltage converter and a voltage detection circuit. The output signal delivered from the voltage detection circuit causes the output voltage from the voltage converter to change in response to the battery voltage so as to reduce electric power consumed by electric circuits.
    Type: Grant
    Filed: June 27, 1978
    Date of Patent: October 7, 1980
    Assignee: Citizen Watch Co., Ltd.
    Inventor: Singo Ichikawa
  • Patent number: 4221111
    Abstract: An electronic timepiece having a voltage conversion circuit for providing a different supply voltage from the timepiece battery voltage, detection means for detecting a condition in which a drive signal of relatively high voltage must be applied to an electromagnetic transducer of the timepiece, which is driven intermittently, switching means controlled by the detection means for selecting either the battery voltage or the converted voltage, and a circuit containing a capacitor which is charged by the output voltage of the switching means while the electromagnetic transducer is not being driven, and is discharged by supplying power to the transducer when the latter is driven, so that drive power is supplied to the transducer from, in effect, a low impedance source.
    Type: Grant
    Filed: August 7, 1979
    Date of Patent: September 9, 1980
    Assignee: Citizen Watch Company Limited
    Inventors: Mitsuo Onda, Singo Ichikawa
  • Patent number: 4219999
    Abstract: An electronic timepiece equipped with a battery life warning system, in which an output voltage of a battery are detected under a heavy load condition and a light load condition. In a first preferred embodiment, a time indicating means effects a display of time in a first predetermined more to provide an initial warning of the battery life when the output voltage drops below a first predetermined level during the heavy load condition and also effects of the display of time in a second predetermined mode to provide a second warning of the battery life when the output voltage of the battery drops below a second predetermined level lower than the first predetermined level.
    Type: Grant
    Filed: March 2, 1978
    Date of Patent: September 2, 1980
    Assignee: Citizen Watch Company, Limited
    Inventors: Singo Ichikawa, Yoshiaki Kato
  • Patent number: 4216649
    Abstract: A function selection circuit for multi-function timepiece which has a timekeeping circuit, a display device to display output data from the timekeeping circuit, and a function circuit to provide a plurality of functions which can be selected by an external control member in a predetermined sequence. The function selection circuit has a circuit means controlled by the external control member to provide an output to enable a selection of time correction mode from said plurality of functions in the predetermined sequence.
    Type: Grant
    Filed: June 30, 1977
    Date of Patent: August 12, 1980
    Assignee: Citizen Watch Company Limited
    Inventors: Singo Ichikawa, Fujio Ishida, Hideyuki Kawashima
  • Patent number: 4178750
    Abstract: A control circuit for an electronic timepiece in which a digit selection switch is connected to a timer circuit which generates an output signal only when the digit selection switch is actuated for a given interval of time. An output signal generation means is coupled to the timer circuit and rendered operative in response to the output signal from the timer circuit to generate an output pulse. A digit selection circuit is responsive to the output pulse from the output signal generation circuit for selecting a digit to be corrected in a timekeeping circuit.
    Type: Grant
    Filed: October 4, 1977
    Date of Patent: December 18, 1979
    Assignee: Citizen Watch Company Limited
    Inventors: Tomomi Murakami, Singo Ichikawa
  • Patent number: 4175377
    Abstract: A timepiece provided with a display device for warning a battery life is disclosed. The timepiece comprises a correction signal control circuit which is controlled by two exteriorly operable switches and which control a battery voltage detection circuit whose sampling operation together with the warning display are interlocked with the operation of one of the exteriorly operable switches which functions as a digit selection switch, correction switch and display change-over switch. A warning display for a short time can be noticed by a bearer by operating the exteriorly operable switch without fail.
    Type: Grant
    Filed: November 4, 1977
    Date of Patent: November 27, 1979
    Assignee: Citizen Watch Co. Ltd.
    Inventor: Singo Ichikawa
  • Patent number: 4173863
    Abstract: An analog quartz timepiece having a manually operated external control member, and a correction signal generation circuit controlled by the external control member to generate low speed and high speed correction signals when the external control member is actuated for a short period of time and for a predetermined time interval, respectively, by which a stepping motor is driven at a selected speed to perform time correction. The timepiece alo includes a click mechanism operative to shift an hours hand step-wise from any optional position without affecting a minutes hand and a seconds hand. The timepiece further includes a seconds zero-reset mechanism operative to reset the seconds hand to zero.
    Type: Grant
    Filed: December 20, 1976
    Date of Patent: November 13, 1979
    Assignee: Citizen Watch Company Limited
    Inventors: Jinro Motoki, Singo Ichikawa, Kenzi Miyasaka, Hiroyuki Uematsu, Mitsuhiro Murata, Hideyuki Kawashima, Yuri Inoue, Masae Ohkubo, Mituo Oooka
  • Patent number: 4147022
    Abstract: An electronic timepiece adapted to perform time correction in response to a train of time correction pulses transmitted from another electronic timepiece. The electronic timepiece comprises a detecting means to detect the train of time correction pulses; a writing-in signal generator circuit to generate writing-in signals in synchronism with a synchronizing signal contained in the train of time correction pulses, and a writing-in gate circuit means to perform writing-in of the train of time correction pulses into a timekeeping circuit of the timepiece as new current time data in response to the writing-in signals.
    Type: Grant
    Filed: September 22, 1976
    Date of Patent: April 3, 1979
    Assignee: Citizen Watch Company Limited
    Inventor: Singo Ichikawa