Patents Assigned to Seiko Koki Kabushiki Kaisha
  • Patent number: 4054892
    Abstract: A camera shutter having an aperture, shutter opening blades which travel from a position covering the aperture to a rest position uncovering the aperture to initiate exposure, and shutter closing blades which travel from a position away from the aperture to a position covering the aperture to terminate exposure, and a shutter blade stabilizing device. The stabilizing device includes an elastic member for frictionally pressing at a leading portion of the shutter opening blades at which the driving force is applied to the blades, when the blades are at the rest position, and a member for pressing against the shutter opening blades at a trailing portion of the blades at a portion where the driving force is applied, when the shutter opening blades are at the rest position. The elastic member and the member for pressing together prevent movement of the shutter opening blades when they are at the rest position.
    Type: Grant
    Filed: December 1, 1975
    Date of Patent: October 18, 1977
    Assignee: Seiko Koki Kabushiki Kaisha
    Inventors: Tadashi Nakagawa, Mitsuo Koyama, Eiichi Onda
  • Patent number: 4054891
    Abstract: In a focal plane camera shutter of the type having opening blades and closing blades which are actuated sequentially to provide an exposure, the opening blades are operated by an operating member which is biased in a direction to move the blades to aperture-closing position. The opening blades are moved to open position when the shutter is released by a driving member which is biased in a direction to open the blades and is releasably connected to the operating member by a connecting member. At approximately the termination of the exposure, the connecting member is actuated to release the blade operating member from the driving member whereupon they are moved by the aforementioned bias to closed position. The camera is then reset by moving the driving member to its set position whereupon the connecting member again connects the driving member with the blade operating member.
    Type: Grant
    Filed: July 23, 1976
    Date of Patent: October 18, 1977
    Assignee: Seiko Koki Kabushiki Kaisha
    Inventors: Eiichi Onda, Masanori Watanabe
  • Patent number: 4053908
    Abstract: In a programming electric shutter for a camera, the photoconductive element receiving light from the subject to be photographed comprises a plurality of photoelectric bodies. An exposure multiple setting device permits using one or more of the photoelectric bodies selectively according to the exposure factors or the sensitivity of the film to be used.
    Type: Grant
    Filed: September 3, 1976
    Date of Patent: October 11, 1977
    Assignee: Seiko Koki Kabushiki Kaisha
    Inventors: Takeo Saito, Yuzuru Takazawa, Shinji Nagaoka, Yoichi Seki
  • Patent number: 4051489
    Abstract: An exposure time control device of an electric camera shutter includes a brightness time conversion circuit for developing a single pulse having a width representative of the brightness of a subject to be photographed and a reference pulse generating circuit for generating reference pulses at a standard rate. A reversible counter counts the reference pulses for a period of time equal to the duration of the single pulse. Upon termination of the single pulse, a reversible counter control circuit applies control signals to the reversible counter to read-out the count stored therein for controlling the shutter exposure time. A selector switch selects the input position of the reference pulses to the reversible counter in dependence upon exposure time factors other than brightness of the subject thereby enabling the selection of the exposure time in accordance with the subject brightness as well as other factors, such as film sensitivity and diaphragm setting.
    Type: Grant
    Filed: May 15, 1975
    Date of Patent: September 27, 1977
    Assignee: Seiko Koki Kabushiki Kaisha
    Inventors: Takeo Saito, Youichi Seki
  • Patent number: 4051498
    Abstract: An electric shutter in which an electrical circuit normally controls the automatic closing of the shutter lens aperture. A mechanical device in the shutter coactive with the electrical circuit closes the shutter lens aperture mechanically, automatically when the electrical circuit is deenergized or because insufficiently energized because of an exhausted power source or because of other reasons.
    Type: Grant
    Filed: August 2, 1974
    Date of Patent: September 27, 1977
    Assignee: Seiko Koki Kabushiki Kaisha
    Inventor: Kiyoshi Kitai
  • Patent number: 4048642
    Abstract: An exposure time control device of an electric shutter includes a brightness-time conversion circuit for developing a single pulse having a width representative of the brightness of a scene to be photographed and a standard pulse generating circuit for generating pulses at a standard rate. A reversible counter counts the standard pulses for a period of time equal to the duration of the single pulse. Upon termination of the single pulse, a reversible counter control circuit applies control signals to the reversible counter to read-out the count stored therein for controlling the shutter exposure time. A delay circuit develops a trigger pulse upon opening of the shutter. The trigger pulse is applied to the reversible counter control circuit, and if it is applied prior to the termination of the single pulse, read-out of the count stored in the reversible counter is initiated prior to termination of the single pulse.
    Type: Grant
    Filed: February 18, 1975
    Date of Patent: September 13, 1977
    Assignee: Seiko Koki Kabushiki Kaisha
    Inventors: Takeo Saito, Youichi Seki
  • Patent number: 4045627
    Abstract: An electrical switch device for detecting preset alarm times in an alarming device comprises a one-piece switch part connected to and rotatable with a rotationally driven time wheel, and first and second fixed switch parts electrically insulated from each other. An alarming circuit is electrically connected to the fixed switch parts and sounds an audible alarm when the switch parts are closed. An alarm time setting mechanism is settable in a predetermined angular position corresponding to the alarm time to be detected so that when the time wheel is driven to the predetermined position, the switch parts are closed thereby activating the alarm.
    Type: Grant
    Filed: April 4, 1975
    Date of Patent: August 30, 1977
    Assignee: Seiko Koki Kabushiki Kaisha
    Inventors: Kiyoshi Kitai, Masuo Ogihara, Kouzo Sato, Nobuo Shinozaki
  • Patent number: 4041511
    Abstract: A lens shutter for a quick-return single-lens reflex camera in which the diaphragm blades and shutter blades are operated by an operating ring driven rotationally in opposite directions by a driving device. The driving device has a pair of axially biased rods that coact to sequence their travel axially in two directions for driving the operating ring through gear racks on one of the rods and a driving ring coupled to the operating ring. A pinion meshes with both gear racks. A stop lever releasably locked by a signal lever stops the operating ring temporarily during taking of an exposure and the signal lever releases the stop lever at the end of an exposure which it signals or indicates. A cocking mechanism comprising a plurality of levers cocks the operating rods to cock the shutter.
    Type: Grant
    Filed: April 18, 1974
    Date of Patent: August 9, 1977
    Assignee: Seiko Koki Kabushiki Kaisha
    Inventors: Kiyoshi Kitai, Yukio Nakamura, Shogo Kato, Shinji Nagaoka
  • Patent number: 4037400
    Abstract: A polarized drive rotor having opposite polarity poles is rotatably arranged in the magnetic field developed by a coreless field coil and a polarized auxiliary rotor also having opposite polarity poles is arranged and magnetically coupled to the drive rotor so as to displace, the drive rotor through a preselected angle with respect to the direction of the magnetic field developed by the coreless field coil. An output is taken out of either one of the polarized rotors to drive a gear train and accordingly drive a clock hand. Electric drive circuitry applies a forward electric current to the field coil to rotationally advance the rotors and after the rotors stop and when a preselected time has passed since the energization of the coil, the rotors are rotated again in the same direction by applying a reverse electric current to the coil. In this way the clock hand can be driven stepwise at intervals of preselected constant time.
    Type: Grant
    Filed: April 6, 1976
    Date of Patent: July 26, 1977
    Assignee: Seiko Koki Kabushiki Kaisha
    Inventors: Kiyoshi Kitai, Masuo Ogihara, Kozo Sato, Nobuo Shinozaki, Yoichi Seki, Yuzuru Takazawa
  • Patent number: 4038675
    Abstract: An electric camera shutter of the type having a digital recording and reproducing system has a self-timer mode and has a counter circuit for counting and memorizing pulses produced by a pulse generator. In one mode of operation, the exposure time is controlled in accordance with the memorized content of the counter circuit and when in the self-timer mode, the output of the counter circuit controls the energization of a self-timer operation indicator circuit which indicates operation in the self-timer mode.
    Type: Grant
    Filed: March 14, 1975
    Date of Patent: July 26, 1977
    Assignee: Seiko Koki Kabushiki Kaisha
    Inventors: Kiyoshi Kitai, Takeo Saito, Youichi Seki
  • Patent number: 4033682
    Abstract: An electric shutter is opened and closed to effect an exposure in dependence upon the energization of an electromagnet. A switching circuit controls the energization of the electromagnet in accordance with various exposure information, such as diaphragm setting and film sensitivity. An exposure control circuit comprised of a series connection of a diode and a variable resistor is connected in parallel with the electromagnet and adjustably controls the time at which the electromagnet is deenergized to accordingly effect closing of the shutter such that the electromagnet delay time equals the shutter sector advancing time to thereby compensate for fluctuations between the two times.
    Type: Grant
    Filed: July 15, 1975
    Date of Patent: July 5, 1977
    Assignee: Seiko Koki Kabushiki Kaisha
    Inventors: Yukio Nakamura, Shougo Kato, Shinji Nagaoka
  • Patent number: 4025929
    Abstract: A shutter control circuit including a brightness-time conversion circuit for developing an output pulse having a duration representative of exposure time, and a standard pulse generating circuit for generating standard pulses at a certain rate. A reversible counter operable in an addition mode and a subtraction mode counts the standard pulses for the duration of the output pulse of the brightness-time conversion circuit so that the number of counted pulses is representative of exposure time. The reversible counter is then operated in a subtraction mode to read-out the counted pulses to control exposure time. The shutter control circuit further includes circuitry for operating the counter in the addition mode and for applying a selectable number of standard pulses to the reversible counter in order to determine exposure time.
    Type: Grant
    Filed: August 23, 1974
    Date of Patent: May 24, 1977
    Assignee: Seiko Koki Kabushiki Kaisha
    Inventors: Takeo Saito, Youichi Seki
  • Patent number: 4019189
    Abstract: A digital exposure time control circuit including a standard pulse generating circuit for developing standard rate pulses which are applied under control of a brightness-time conversion circuit to a dividing circuit, and subsequently counted in a reversible counter operating in a counting mode. The number of standard pulses counted are controlled by the brightness-time conversion circuit to be proportional to an exposure time, and the counted pulses are subsequently read-out from the counter to control exposure time. The exposure time control circuit also includes a self-timer control circuit which is responsive to a predetermined number of counted pulses to clear the reversible counter, and enable the brightness-time conversion circuit when the number of counted pulses exceeds the predetermined number in order to develop a delay time, determined by the predetermined number of pulses to which the self-timer is responsive, before the start of counting the pulses for controlling exposure time.
    Type: Grant
    Filed: February 14, 1975
    Date of Patent: April 19, 1977
    Assignee: Seiko Koki Kabushiki Kaisha
    Inventors: Kiyoshi Kitai, Takeo Saito, Youichi Seki
  • Patent number: 4015417
    Abstract: An alarming device for a clock comprises a manual selector for setting the desired alarm time. An alarm time setting detecting mechanism coacts with the rotationally driven time wheels of the clock for detecting the preset alarm time and thereafter actuates an audible alarm. An alarm time indicating mechanism provides a visual indication of the preset alarm time and includes a notifying mechanism which provides a visual indication indicative of the operative or inoperative state of the alarming device thereby notifying the user as to whether or not the device is set to detect an alarm time. The notifying mechanism comprises ON and OFF indicia which may be selectively illuminated or which may be selectively covered by a masking plate to provide the visual indication.
    Type: Grant
    Filed: April 7, 1975
    Date of Patent: April 5, 1977
    Assignee: Seiko Koki Kabushiki Kaisha
    Inventors: Kiyoshi Kitai, Masuo Ogihara, Kouzo Sato, Nobuo Shinozaki
  • Patent number: 4015142
    Abstract: Electric timing circuitry for a camera comprises a series connection of a resistor and capacitor with the junction point of the two being connected to the input of a switching circuit. A series circuit composed of a starting switch for initiating the timing cycle and a source switch for connecting the circuitry to a source of electric energy is connected in parallel with the capacitor. The single capacitor performs the dual role of functioning as a timing capacitor and compensating for switch chatter of the source switch.
    Type: Grant
    Filed: September 2, 1975
    Date of Patent: March 29, 1977
    Assignee: Seiko Koki Kabushiki Kaisha
    Inventors: Shinji Nagaoka, Yuzuru Takazawa
  • Patent number: 3999191
    Abstract: An electronic camera shutter control circuit having a reversible counter for counting a number of pulses proportional to the duration of an exposure time. When the camera shutter is opened pulses are subtracted from the memory content of the reversible counter until the counter content is zero and the exposure is terminated. The reversible counter includes a final stage which does not change state if the number of pulses applied to the counter exceeds the memory capacity of the counter. For this condition the exposure time is first controlled by the charging time of a capacitor until a voltage stored in the capacitor exceeds a certain value whereupon the memory content of the counter is subtracted until it is zero and the exposure is terminated.
    Type: Grant
    Filed: August 23, 1974
    Date of Patent: December 21, 1976
    Assignee: Seiko Koki Kabushiki Kaisha
    Inventors: Takeo Saito, Youichi Seki
  • Patent number: 3996734
    Abstract: An alarming device for a clock comprises a rotationally driven minute time wheel having plural sets of shift teeth, a rotatable 10-minutes time wheel which intermittently meshes with the shift teeth of the minute time wheel to be driven thereby, and a rotatable hour time wheel which intermittently meshes with the 10-minutes time wheel and is driven thereby. First and second detection devices respectively detect when the 10-minutes and hour time wheels are in predetermined angular positions, and setting means enables setting of the detection devices in predetermined positions. An audible alarm is rendered operative and provides an audible alarm only when the 10-minutes time wheel and the hour time wheel have respectively conformed in phase with said first and second detection devices thereby providing notification of the alarm time.
    Type: Grant
    Filed: April 23, 1975
    Date of Patent: December 14, 1976
    Assignee: Seiko Koki Kabushiki Kaisha
    Inventors: Kiyoshi Kitai, Masuo Ogihara, Kouzo Sato, Nobuo Shinozaki
  • Patent number: 3988750
    Abstract: An exposure time indicating apparatus for a camera shutter having a switching circuit that has a switching level which is compensated for the brightness of an object or field of exposure. The apparatus includes an indicating circuit that indicates the exposure time. The signal developed to indicate the exposure time takes into consideration exposure factors other then the delay for variaions in brightness, for control of exposure time. This other factor is introduced by camera adjustments which effect automatically adjustment of a variable resistor as a function of the exposure factor being adjusted and this resistor varies a bias voltage on a transistor of a differential amplifier for varying the output thereof to apply a variation to a switching circuit controlling the shutter to change its switching level and the switching signal closing the shutter. This varied and time-delayed signal is visually indicated in a meter as the actual exposure time before the taking of an exposure.
    Type: Grant
    Filed: May 13, 1975
    Date of Patent: October 26, 1976
    Assignee: Seiko Koki Kabushiki Kaisha
    Inventor: Takeo Saito
  • Patent number: 3987464
    Abstract: An electronic camera shutter control circuit having an indicator for indicating when the camera shutter is open. A circuit responsive to a control signal controls a current flow through an electromagnet which is energized during the opening of the camera shutter to prevent the shutter release mechanism from closing the shutters. An indicating element indicates that current is flowing through the electromagnet and therefore indicates that the shutter is open. A control circuit having a photoresponsive element develops a control signal determined by the brightness of the scene to be photograhed and applies the control signal to the circuit responsive to the control signal. The control circuit includes a capacitor which is charged at a rate determined by the conductivity of the photoresponsive element which varies according to the light sensed.
    Type: Grant
    Filed: December 23, 1974
    Date of Patent: October 19, 1976
    Assignee: Seiko Koki Kabushiki Kaisha
    Inventors: Kiyoshi Kitai, Yuzuru Takazawa
  • Patent number: 3978498
    Abstract: An exposure time control circuit for an electric shutter of a camera includes a monolithic IC having input circuitry in the form of a transistorized differential amplifier having two input terminals. A time-constant circuit develops a timing signal proportional to the brightness of the object field and applies it to one input terminal and a reference voltage signal is applied to the other input terminal to control the exposure timing. In order to enable varying the reference voltage through a wide range so that the input terminals can also be used for introducing other exposure information variables, such as input signals representative of the F-value, film sensitivity, etc., a transistor is connected between the IC and the source of electric power.
    Type: Grant
    Filed: February 5, 1975
    Date of Patent: August 31, 1976
    Assignee: Seiko Koki Kabushiki Kaisha
    Inventors: Yukio Nakamura, Shogo Kato, Shinji Nagaoka