Patents Assigned to Citizen Watch Company
  • Multi-layer display device with nonactive display element groups
    Patent number: 4443062
    Abstract: In a multi-layer display device such as a liquid crystal display, each of a plurality of sets of display elements is defined by a corresponding common electrode and a plurality of segment electrodes. Segment electrodes of sets of display elements which will not be activated simultaneously are connected together, with at least one of these sets being maintained in a deactivated state by means of a special drive signal applied to the corresponding common electrode. The level of time-sharing which must be utilized for driving the various common electrodes, for a given number of external connections to the segment electrodes, can thereby be reduced, or the overall number of connections made to the display device can be substantially reduced.
    Type: Grant
    Filed: September 16, 1980
    Date of Patent: April 17, 1984
    Assignee: Citizen Watch Company Limited
    Inventors: Seigo Togashi, Akira Tsuzuki, Hiro Fujita
  • Electronic timepiece
    Patent number: 4441826
    Abstract: An electronic timepiece having voltage regulation, temperature detection and battery voltage detection means provided on the same integrated circuit as is used for timekeeping circuitry, and having external terminals for stepwise weighted adjustment of timekeeping gain/loss.
    Type: Grant
    Filed: September 30, 1982
    Date of Patent: April 10, 1984
    Assignee: Citizen Watch Company Limited
    Inventors: Shigeru Morokawa, Keiichiro Koga
  • Movement structure for an electronic timepiece
    Patent number: 4437768
    Abstract: An improved structure is disclosed for the movement of an electronic quartz crystal controlled wristwatch of very small size, suitable for use as a ladies bracelet timepiece. The configuration of this structure is such that a relatively large capacity battery can be utilized, thereby ensuring satisfactory battery life, by positioning the battery such as to substantially cover the wheel train of the timepiece and by a special arrangement of shapes and positions for other components of the timepiece.
    Type: Grant
    Filed: April 7, 1981
    Date of Patent: March 20, 1984
    Assignee: Citizen Watch Company Limited
    Inventor: Kenji Miyasaka
  • Liquid crystal display device
    Patent number: 4435046
    Abstract: A liquid crystal display cell of annular form is provided with a central aperture to accommodate an analog time display section having time indicating hands. The annular liquid crystal cell is characterized in that a plurality of common electrodes are provided on one substrate of the cell, to enable multiplexed drive of the display elements of the cell. Each of the plurality of common electrode comprises a plurality of separate common electrode portions which are electrically connected by connecting lead portions. Half of the connecting lead portions can be arranged to be outside the display area of the cell, thereby enabling the available display area to be maximized.
    Type: Grant
    Filed: April 6, 1981
    Date of Patent: March 6, 1984
    Assignee: Citizen Watch Company Limited
    Inventor: Katsuo Nishimura
  • Liquid crystal display device for world time wristwatch
    Patent number: 4435086
    Abstract: A liquid crystal display device for a world time electronic timepiece in which a display of world time is made by a liquid crystal display device, with various locations on a world map being selectable for display of local time, a corresponding marker on the world map being caused to flash to indicate selection and the name of the selected location being displayed in abbreviated form simultaneously with the local time at the selected location.
    Type: Grant
    Filed: July 16, 1981
    Date of Patent: March 6, 1984
    Assignee: Citizen Watch Company Limited
    Inventor: Yoshiaki Kato
  • Electronic timepiece having improved primary frequency divider response characteristics
    Patent number: 4433920
    Abstract: In an electronic timepiece having a primary frequency divider circuit coupled to receive a standard frequency signal and comprising a group of P-channel FETs and a group of N-channel FETs, a bias circuit supplies a bias input to the P-channel FET group and a separate bias input to the N-channel FET group. By providing these bias inputs through current mirror coupling from a standard current source, the response of the primary frequency divider circuit to low amplitudes of the standard frequency signal can be made substantially independent of timepiece battery voltage variations, over a wide range of battery voltages.
    Type: Grant
    Filed: July 7, 1981
    Date of Patent: February 28, 1984
    Assignee: Citizen Watch Company Limited
    Inventors: Fukuo Sekiya, Shigeru Morokawa, Ryoji Iwakura
  • Analog display electronic timepiece with multi-mode display capability
    Patent number: 4433918
    Abstract: An electronic timepiece of analog display type is provided with at least one other additional function mode such as an alarm mode in addition to a current time mode of operation. When changeover from one function mode to another is performed, by actuation of an external operating member, information indicated by the timepiece analog display is rapidly changed over to correspond to information for the new function mode, e.g. is rapidly changed over to indicate an alarm time when changeover from the current time mode to the alarm time mode is performed, and rapidly changed to indicate current time when the reverse mode changeover is performed.
    Type: Grant
    Filed: July 7, 1981
    Date of Patent: February 28, 1984
    Assignee: Citizen Watch Company Limited
    Inventors: Katsuo Nishimura, Fukuo Sekiya
  • Combination matrix array display and memory system
    Patent number: 4430648
    Abstract: A display device of solid-state matrix type, such as a liquid crystal display device, retains display data for an unlimited period after such data has been written into the display, with no need for periodic re-writing of the display data to compensate for deterioration due to leakage effects. In addition, the display data can be read out again, if required, so that the display device can also be used as a memory. such a display device can also be utilized to perform data input, by writing in of data through application of light to the display surface, such as by using a light pen.
    Type: Grant
    Filed: January 12, 1981
    Date of Patent: February 7, 1984
    Assignee: Citizen Watch Company Limited
    Inventors: Seigo Togashi, Akira Tsuzuki
  • Timekeeping signal source for an electronic timepiece
    Patent number: 4427302
    Abstract: A timekeeping signal source for an electronic timepiece produces a highly accurate timekeeping signal which is stable in frequency with respect to both temperature variations and long-term drift. The timekeeping signal is produced by phase lock control using a high frequency reference signal from a crystal-controlled high-frequency oscillator. Phase lock control can be performed continuously or on an intermittent basis, in order to reduce power consumption. In addition, the timekeeping rate can be adjusted with a resolution within one period of the high frequency reference signal, by variation of a numeric value stored in digital memory means.
    Type: Grant
    Filed: June 1, 1981
    Date of Patent: January 24, 1984
    Assignee: Citizen Watch Company Limited
    Inventor: Shinichi Watanabe
  • Electronic timepiece having illumination level
    Patent number: 4423963
    Abstract: An electronic timepiece is provided with a photo-electric cell generating an output voltage indicative of incident illumination levels, circuit means for converting this output voltage into digital data signals, and a liquid crystal display which is driven in response to the data signals such that successive sections of the display act to progressively unmask a rear reflector plate to thereby indicate the illumination level. The circuits for converting illumination level to data signals are based on an oscillator circuit whose frequency is controlled by the photo-electric cell voltage, and digital means for measuring this frequency, so that the circuit configuration is very simple and power comsumption extremely low.
    Type: Grant
    Filed: September 15, 1982
    Date of Patent: January 3, 1984
    Assignee: Citizen Watch Company Limited
    Inventor: Fuminori Suzuki
  • Table apparatus
    Patent number: 4423686
    Abstract: A table apparatus provided with a stacked array of upper and lower slides which are driven independently of each other, in which at least one slide surface of the lower slide is a slide guide shaft which is reciprocatively rotatable and which has a non-circular cross-section, and in which there are provided a rotation transmission mechanism disposed on the table of the lower slide and engaging with the slide guide shaft, said transmission mechanism being slidable axially of the slide guide shaft and rotatable along with said slide guide shaft, and an upper slide drive mechanism for sliding the upper slide in response to the rotation of said rotation transmission mechanism.
    Type: Grant
    Filed: December 23, 1981
    Date of Patent: January 3, 1984
    Assignee: Citizen Watch Company Limited
    Inventors: Katumi Ueno, Genichi Nishizaki
  • Analog display type electronic timepiece
    Patent number: 4419019
    Abstract: An analog display type of electronic timepiece is provided with an alarm function, whereby changeover can be rapidly performed between display of current time and of a preset alarm time, by rapid rotation of the timepiece hands, and features means whereby the hands are advanced in steps of less than one minute during the current time display state but are advanced by steps of precisely one minute while setting of an alarm time is being carried out, so that the alarm time is precisely set with the minutes hand positioned at a minutes graduation on the dial.
    Type: Grant
    Filed: April 14, 1982
    Date of Patent: December 6, 1983
    Assignee: Citizen Watch Company Limited
    Inventors: Katsuo Nishimura, Minoru Watanabe
  • Structure of push-button device
    Patent number: 4417113
    Abstract: In a push-button device having a waterproofing O-ring disposed between the inner wall of a pipe and the shaft portion of a button body, the structure of said push-button device characterized in that a non-metallic, resilient sleeve for preventing the invasion of dust and for restoring the push-button is disposed in a clearance formed between the head portion of the button body and a stepped portion provided on said inner wall of said pipe.
    Type: Grant
    Filed: February 5, 1981
    Date of Patent: November 22, 1983
    Assignee: Citizen Watch Company Limited
    Inventors: Motoyuki Saito, Satoru Fukutome
  • Numerically controlled lathe
    Patent number: 4413539
    Abstract: In a numerically controlled lathe, two guide bars are located in front of a headstock and extending parallel to the axis of a spindle to guide a saddle theroen. A cross slide is slidably supported by a guideway of the saddle to move a pair of turret heads in a direction perpendicular to the axis of the spindle. Turret indexing means allows indexing of one of the turret heads while a tool receiver fixed on the other turret head assumes in a predetermined cutting area relaive to the axis of the spindle. The saddle has a chip dropping wall formed between a guide bush and the pair of turret heads, with a front portion of the chip dropping wall downwardly slanting toward the front side of the lathe.
    Type: Grant
    Filed: October 29, 1980
    Date of Patent: November 8, 1983
    Assignee: Citizen Watch Company Limited
    Inventors: Shinichi Ishizuka, Kenji Sugimoto
  • Joint structure of bezel and watch body
    Patent number: 4408900
    Abstract: A joint structure of a watch body and a bezel comprising a watch body with a joint surface, a bezel with a joint surface, at least one projection extending from one of the joint surfaces welded onto the other surface, a space between said surfaces and connecting material filling said space. By thus constructing, the watch body and bezel have a durable water and air tight joint.
    Type: Grant
    Filed: April 17, 1981
    Date of Patent: October 11, 1983
    Assignee: Citizen Watch Company Limited
    Inventors: Tsuneji Takasugi, Seiji Umezawa
  • Method of manufacturing a timepiece component
    Patent number: 4404067
    Abstract: A method of manufacturing components of a timepiece dial, such as timekeeping hands and dial plates, whereby these components can be made extremely thin, while warping is held to a very low level even if the component is subjected to machining operations. The method is based upon utilizing a plurality of electroformed metal layers having different types of internal stress, i.e.
    Type: Grant
    Filed: March 16, 1982
    Date of Patent: September 13, 1983
    Assignee: Citizen Watch Company Limited
    Inventor: Tadao Enomoto
  • Digital-analog converter circuit for speech-synthesizing electronic timepiece
    Patent number: 4397562
    Abstract: A novel type of digital-to-analog converter circuit is disclosed for an electronic timepiece having a speech synthesizing capability. The converter circuit utilizes pulse width modulation to form a train of pulses in response to successive digital signals which specify amplitude and polarity values for synthesizing speech, with the pulse widths being determined in accordance with the digital signal values. By filtering out the unwanted high frequency components of this pulse train, speech signals can be synthesized through an audio transducer. Such a digital-to-analog converter is capable of operating in a satisfactory manner at low levels of supply voltage, and has a very low power consumption.
    Type: Grant
    Filed: February 24, 1981
    Date of Patent: August 9, 1983
    Assignee: Citizen Watch Company Limited
    Inventor: Shinichi Shirasu
  • Timepiece push-button structure
    Patent number: 4397568
    Abstract: A timepiece push-button structure comprising a spring member composed of tongue portions interconnected by a connection portion, each tongue portion being bridge-shaped so that the central portion is raised while both end portions of the central portion abut against a pressure conductive rubber holder, each tongue portion further including a substantially centrally located arcuate notch and a bifurcation extending therefrom. A push-button having a groove is adapted to engage said notch, and a pressure conductive rubber is adapted for the application of pressure and disposed directly below the push-button.
    Type: Grant
    Filed: April 3, 1981
    Date of Patent: August 9, 1983
    Assignee: Citizen Watch Company Limited
    Inventors: Masahiko Waki, Hisao Yamagata, Toshio Murata, Fumio Takeuchi, Masataka Matsumoto
  • Electronic pace timing device
    Patent number: 4396904
    Abstract: An electronic pace timing device whereby a physically perceptible pace timing signal can be repetitively generated, and whereby the repetition frequency of this pace timing signal can be set into the pace timing device as a numeric value, by actuation of external operating members. No calculations are performed in order to convert the numeric value specifying the repetition frequency of the pace timing signal into an actual pace timing signal, so that the overall circuit configuration can be very simple.
    Type: Grant
    Filed: April 1, 1981
    Date of Patent: August 2, 1983
    Assignee: Citizen Watch Company Limited
    Inventor: Tadashi Hanaoka
  • Correction system for electronic timepiece with both analog and digital displays
    Patent number: 4396294
    Abstract: In an electronic timepiece equipped with both an analog display section having time indicating hands and a digital display section, a time correction system is provided whereby correction of both the analog and digital time displays can be performed by rotation of a crown, with the directions of rotation of the crown for time data incrementation and decrementation being identical both for analog and digital display correction. Selection of either analog time correction or digital time correction is performed simply by pulling the crown out to either of two axial positions. Correction of both analog and digital time display information is thereby simplified and made more rapid, while the number of external operating members is reduced.
    Type: Grant
    Filed: February 11, 1981
    Date of Patent: August 2, 1983
    Assignee: Citizen Watch Company Limited
    Inventor: Masaru Yoshida