Patents by Inventor Isao Kitazawa

Isao Kitazawa 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: 7961557
    Abstract: An analog electronic watch of the present invention includes: a display unit (2) for displaying time with a position of a hand; a stepper motor (3) for driving the hand; a motor drive unit (4) for controlling driving of the stepper motor at a predetermined hand drive cycle at normal time; hand position detection means (5) for detecting a position of the hand; a hand position detection means control unit (6) for intermittently controlling driving of the hand position detection means (5) at a first detection cycle which is longer than the hand drive cycle; and a detection cycle changing unit (7) for instructing the hand position detection means (5) to change the detection cycle.
    Type: Grant
    Filed: March 2, 2007
    Date of Patent: June 14, 2011
    Assignee: Citizen Holdings Co., Ltd.
    Inventors: Teruhiko Fujii, Isao Kitazawa, Masaaki Namekawa, Takayuki Uchida, Takayuki Hasumi, Takuji Ike
  • Patent number: 7701807
    Abstract: Impact detecting resistors (141), (143) of an impact detecting circuit (104) detect a counter electromotive force of a step motor (105) generated due to an impact. This counter electromotive force is amplified applying a predetermined period and a predetermined chopper-width by a chopper-amplifying waveform shaping circuit (118). Therefore, even a light impact can be detected. Inverters (145), (146) compare these impact detecting signals (S22), (S23) with a threshold value and detect an impact when the signals exceeds the threshold value. A controlling circuit (102) provides a lock pulse to the step motor (105) through signal lines (AA), (BB) when an impact is detected, brakes rotation of a rotor (162) thereby preventing a deviation of the time displayed with a second hand (106).
    Type: Grant
    Filed: November 29, 2004
    Date of Patent: April 20, 2010
    Assignee: Citizen Holdings Co., Ltd.
    Inventors: Isao Kitazawa, Akiyoshi Murakami, Haruhiko Higuchi
  • Publication number: 20090016172
    Abstract: An analog electronic watch of the present invention includes: a display unit (2) for displaying time with a position of a hand; a stepper motor (3) for driving the hand; a motor drive unit (4) for controlling driving of the stepper motor at a predetermined hand drive cycle at normal time; hand position detection means (5) for detecting a position of the hand; a hand position detection means control unit (6) for intermittently controlling driving of the hand position detection means (5) at a first detection cycle which is longer than the hand drive cycle; and a detection cycle changing unit (7) for instructing the hand position detection means (5) to change the detection cycle.
    Type: Application
    Filed: March 2, 2007
    Publication date: January 15, 2009
    Inventors: Teruhiko Fujii, Isao Kitazawa, Masaaki Namekawa, Takayuki Uchida, Takayuki Hasumi, Takuji Ike
  • Publication number: 20070115760
    Abstract: Impact detecting resistors (141), (143) of an impact detecting circuit (104) detect a counter electromotive force of a step motor (105) generated due to an impact. This counter electromotive force is amplified applying a predetermined period and a predetermined chopper-width by a chopper-amplifying waveform shaping circuit (118). Therefore, even a light impact can be detected. Inverters (145), (146) compare these impact detecting signals (S22), (S23) with a threshold value and detect an impact when the signals exceeds the threshold value. A controlling circuit (102) provides a lock pulse to the step motor (105) through signal lines (AA), (BB) when an impact is detected, brakes rotation of a rotor (162) thereby preventing a deviation of the time displayed with a second hand (106).
    Type: Application
    Filed: November 29, 2004
    Publication date: May 24, 2007
    Inventors: Isao Kitazawa, Akiyoshi Murakami, Haruhiko Higuchi
  • Patent number: 7161874
    Abstract: The power generated by a power generating means (1) of a power-generating type electronic clock is measured by a first power generating sensing means (101) and a second power generating sensing means (102). The power generation level required when the operation is changed from a normal mode to a power-saving mode and the power generation level required when the operation is changed from the power-saving mode back to the normal mode are made different to prevent the phenomenon that the operation changes frequently by imparting hysteresis characteristics to the power generation level which causes a change in the mode, thereby improving the power-saving effect.
    Type: Grant
    Filed: June 21, 2001
    Date of Patent: January 9, 2007
    Assignee: Citizen Watch Co., Ltd.
    Inventors: Masakazu Ichikawa, Isao Kitazawa
  • Patent number: 6876602
    Abstract: A first voltage detector detects whether the voltage of a secondary cell has reached to 1.2V and a first timer counts a time duration for which the voltage is equal to or above 1.2V. If the time counted by the first timer reaches one hour, a second timer starts counting time for one hour. An amount of charge accumulated in the secondary cell is displays after counting of the one hour by the second timer is over. As a result, an accurate display of the amount of charge accumulated in the secondary cell can be achieved.
    Type: Grant
    Filed: February 19, 2003
    Date of Patent: April 5, 2005
    Assignee: Citizen Watch Co., Ltd.
    Inventors: Masakazu Ichikawa, Isao Kitazawa, Masao Sakuyama, Tomio Okigami
  • Publication number: 20030235117
    Abstract: A first voltage detector detects whether the voltage of a secondary cell has reached to 1.2V and a first timer counts a time duration for which the voltage is equal to or above 1.2V. If the time counted by the first timer reaches one hour, a second timer starts counting time for one hour. An amount of charge accumulated in the secondary cell is displays after counting of the one hour by the second timer is over. As a result, an accurate display of the amount of charge accumulated in the secondary cell can be achieved.
    Type: Application
    Filed: February 19, 2003
    Publication date: December 25, 2003
    Applicant: CITIZEN WATCH CO., LTD.
    Inventors: Masakazu Ichikawa, Isao Kitazawa, Masao Sakuyama, Tomio Okigami
  • Patent number: 6593901
    Abstract: An electronic device provided with a multilayer display panel (60), in which during information display by any display panel layer (1 or 2) of the multilayer display panel (60), display driving means (40) maintains all the display segments of the other display panel layer (1 or 2) to be off, allowing simple display control.
    Type: Grant
    Filed: October 3, 2000
    Date of Patent: July 15, 2003
    Assignee: Citizen Watch Co., Ltd.
    Inventors: Isao Kitazawa, Tomio Okigami, Hiroshi Fujioka, Takashi Osa, Masahiro Sase
  • Publication number: 20030081507
    Abstract: A display section has an information display section, a city display section, and a time difference display section. A mode switch designates information to be displayed in the information display section. A time counter counts a certain time. A desired time zone is designated using a push switch. A time computer calculates a time difference between the counted time and the time in the designated time zone. A display controller controls the display section to display the designated information in the information display section, and the information on the time zone and the information on the time difference in the time difference display section.
    Type: Application
    Filed: October 21, 2002
    Publication date: May 1, 2003
    Applicant: Citizen Watch Co., Ltd.
    Inventor: Isao Kitazawa
  • Publication number: 20020183865
    Abstract: The power generated by a power generating means (1) of a power-generating type electronic clock is measured by a first power generating sensing means (101) and a second power generating sensing means (102). The power generation level required when the operation is changed from a normal mode to a power-saving mode and the power generation level required when the operation is changed from the power-saving mode back to the normal mode are made different to prevent the phenomenon that the operation changes frequently by imparting hysteresis characteristics to the power generation level which causes a change in the mode, thereby improving the power-saving effect.
    Type: Application
    Filed: July 2, 2002
    Publication date: December 5, 2002
    Inventors: Masakazu Ichikawa, Isao Kitazawa
  • Patent number: 6185158
    Abstract: A small electronic apparatus provided with a functional display unit is formed of function driving device for generating function driving signals corresponding to a plurality of functions, a plurality of functional display devices corresponding to the functions and including first and second display devices, and a single motor electrically connected to the function driving devices and operated according to the function driving signals from the function driving device. A driving device transmits a driving force to the first functional display device, and an intermittent driving device is connected to the driving device to operate in association therewith. The intermittent driving device rotates the second display device intermittently. A clocking device is electrically connected to the function driving device.
    Type: Grant
    Filed: April 30, 1998
    Date of Patent: February 6, 2001
    Assignee: Citizen Watch Co., Ltd.
    Inventors: Yukio Ito, Tomio Okigami, Isao Kitazawa