Patents by Inventor Zenzo Nakamura

Zenzo Nakamura 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: 4669850
    Abstract: An exposure control system for daylight and flash photography. In the flash mode with computer flash light device, the system accommodates for a variation in the otherwise fixed parameter of diaphragm aperture by taking into account the camera-to-subject distance. In one embodiment of the invention, the diaphragm value and the integrated flash light are varied with distance at equal rates to each other, reaching the maximum possible values simultaneously at a distance twice as long as that when the diaphragm is fixed. In another embodiment, these variables are increased one at a time, reaching the maximum value, after which the other is increased to effect an equivalent result.
    Type: Grant
    Filed: February 19, 1986
    Date of Patent: June 2, 1987
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takashi Uchiyama, Ryoichi Suzuki, Zenzo Nakamura
  • Patent number: 4464609
    Abstract: A voltage detecting means is provided in a flash lamp firing circuit for detecting the attainment of the voltage of a storage capacitor to a satisfactory lamp firing voltage level to assure that a photographic camera associated with the flash lighting unit operates in a flash exposure range switched from a daylight exposure range only when a sufficient voltage is available to fire the lamp at the time of striking of the lamp.
    Type: Grant
    Filed: November 14, 1983
    Date of Patent: August 7, 1984
    Assignee: Canon Kabushiki Kaisha
    Inventors: Zenzo Nakamura, Takashi Uchiyama, Shohei Ohtaki, Tokuichi Tsunekawa, Masanori Uchidoi, Yukio Mashimo
  • Patent number: 4449802
    Abstract: An adapter device for interconnecting a light adjusting flash device and a camera. The adapter device includes a first terminal for connection to a charge completion signal circuit in the flash device, a second terminal for connection to a mode selection circuit in the camera and a transistor which is turned on in response to a charge completion signal to change the electrical condition at the second terminal to operate the mode selecting circuit to select the flashlight mode. The adapter device further includes a third terminal which is connected to an aperture signal forming circuit in the camera and is connectable to the second terminal to transmit a flash aperture value signal to an aperture control circuit in the camera.
    Type: Grant
    Filed: June 21, 1983
    Date of Patent: May 22, 1984
    Assignee: Canon Kabushiki Kaisha
    Inventor: Zenzo Nakamura
  • Patent number: 4382666
    Abstract: An indicating device of computer type electronic flash apparatus has a plurality of display members representing respective limited distance ranges for correct exposure of an object to be photographed. Each of the display members corresponds to a respective set diaphragm value. The indicating device further includes a plurality of indicating marks provided on the same plane of said display members and corresponding to respective set diaphragm values. With this device, it is possible to be aware of the proper distance range satisfactorily.
    Type: Grant
    Filed: November 12, 1980
    Date of Patent: May 10, 1983
    Assignee: Canon Kabushiki Kaisha
    Inventors: Shohei Ohtaki, Zenzo Nakamura, Naoki Nagase
  • Patent number: 4315679
    Abstract: An adapter device for use with a versatile light adjusting flash illuminating device of the reflected light reception type or a slightly reformed flash illuminating device receives a light emission preparation signal of the flash illuminating device, for example, the charging completion signal of a main capacitor or a main switch ON signal and forms an exposure control signal for an exclusive camera. The adapter device is provided with a shoe for accommodating the leads of the flash unit and with a foot for connection with the leads of the exclusive camera.
    Type: Grant
    Filed: September 27, 1979
    Date of Patent: February 16, 1982
    Assignee: Canon Kabushiki Kaisha
    Inventor: Zenzo Nakamura
  • Patent number: 4238149
    Abstract: A shutter control circuit which normally responds to ambient light switches automatically to a flash mode in response to a charge signal from a flash unit. The light flash eliminates the charge signal. To prevent the absence of a charge signal from returning the shutter to daylight control, a shutter closing signal is generated before a flash synchronizing contact is closed and hence before the charge signal ends. However shutter closing action is then started only after a delay that provides time for the flash to occur when the shutter is fully open.
    Type: Grant
    Filed: July 28, 1978
    Date of Patent: December 9, 1980
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takashi Uchiyama, Shohei Ohtaki, Zenzo Nakamura, Tokuichi Tsunekawa, Tadashi Ito, Hiroshi Aizawa
  • Patent number: 4230402
    Abstract: The present invention relates to a device for flash light photography and, more particularly, to a device for flash light photography for adjustable light stroboscope. A major feature of the present invention is that the adjustable light condition of the stroboscope is rendered to be adjusted, based on the film speed and diaphragm value, independently of each other. Thus, when the film speed is made high, the responsive distance for light adjustment is elongated.
    Type: Grant
    Filed: March 3, 1978
    Date of Patent: October 28, 1980
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takashi Uchiyama, Zenzo Nakamura, Shohei Ohtaki
  • Patent number: 4200370
    Abstract: An automatic exposure control system for cameras of flash photographic capabilities which is switched to either of the daylight or the mode depending upon whether or not a storage capacitor across which a flash tube is connected is sufficiently charged. The system comprises first and second computers for deriving daylight and flash exposure aperture values respectively, a diaphragm control circuit selectively receptive of the outputs of the computers through a first switch, first and second timing circuits for providing daylight and flash exposure times respectively, and a shutter control circuit selectively receptive of the outputs of the timing circuits through a second switch. The system is characterized in the use of a single mode selection actuator which is common to the first and second switches and which causes an automatic selection of the flash mode when the camera release occurs after the attainment of the voltage of the storage capacitor to the normal firing level.
    Type: Grant
    Filed: October 13, 1978
    Date of Patent: April 29, 1980
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hiroshi Aizawa, Masanori Uchidoi, Zenzo Nakamura, Yoshiyuki Takishima
  • Patent number: 4187019
    Abstract: The present invention relates to various kinds of the flash light photographic systems consisting of a combination of either of the below mentioned cameras with either of the below mentioned flash light device;a camera CD presenting an input terminal of the information for controlling the diaphragm and the output terminal of the information for the set aperture,a flash light device SD presenting the output terminal of the information for controlling the diaphragm and the input terminal of the information of the set aperture,a camera CT presenting an input terminal of the information for controlling the diaphragm,a camera CA presenting an output terminal of the information of the set aperture,a flash light device ST presenting an output terminal of the information for controlling the diaphragm,a flash light device AS presenting an input terminal of the information of the set aperture.
    Type: Grant
    Filed: August 12, 1977
    Date of Patent: February 5, 1980
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takashi Uchiyama, Zenzo Nakamura, Tokuichi Tsunekawa, Masanori Uchidoi, Yukio Mashimo, Shyohei Ohtaki
  • Patent number: 4181416
    Abstract: A photographic data recording device for a camera for photographically recording some data on film together with a photographic image. The device includes a capacitor, a charging circuit for the capacitor which responds to the release of the shutter for commencing charging and an electronic flash device operating in response to the capacitor discharge to illuminate the data. A control device automatically causes the capacitor to discharge electricity to allow the electronic flash device to emit a flash when the charge of the capacitor reaches a preset level of potential and which prevents the capacitor from discharging when the charge is below the preset level of potential. A display lamp may be utilized to indicate when the charged voltage of the capacitor reaches a preset level.
    Type: Grant
    Filed: October 13, 1976
    Date of Patent: January 1, 1980
    Assignee: Canon Kabushiki Kaisha
    Inventors: Syohei Ohtaki, Keiko Kondo, Zenzo Nakamura, Youichi Okuno
  • Patent number: 4168891
    Abstract: A camera having an electronic flash unit either incorporated therein or removably attached thereto is provided with a flash mode selector and a flash energy supply control switch both arranged to be rendered operative when the shutter cocking lever is pulled from the retracted position to an initial position effective for shutter cocking operation, and, upon detection of occurrence of a lower light value beyond an automatically operating daylight diaphragm aperture range, to be simultaneously closed in automatic response to an actuation of a shutter release trigger in excess of a normal stroke length. This is done while still preventing the shutter from running. When the voltage on a storage capacitor reaches a trigger level for the flash tube in a time interval measuring from the closure of the switch, a flash exposure diaphragm aperture is automatically formed depending upon the flash exposure value and the voltage of the storage capacitor.
    Type: Grant
    Filed: May 17, 1977
    Date of Patent: September 25, 1979
    Assignee: Canon Kabushiki Kaisha
    Inventors: Michio Hirohata, Mutsuhide Matsuda, Zenzo Nakamura
  • Patent number: 4162426
    Abstract: The present invention relates to a light-sensing circuit used in a so-called light regulating type flash device to automatically control the amount of flash emitted. In the present invention, a flash photographing with an appropriate exposure is done, securing such flash amount as providing appropriate exposure always regardless of the position of an object in a photographing frame. This is done by making light-sensing for each of different zones independently using a plural number of light-sensing circuits for stopping the flashing by the output of the one light-sensing circuit reaching a prescribed level of output from the different light-sensing circuits.
    Type: Grant
    Filed: December 21, 1977
    Date of Patent: July 24, 1979
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tokuichi Tsunekawa, Zenzo Nakamura, Osamu Okubo, Takashi Uchiyama
  • Patent number: 4127325
    Abstract: A self-adjusting electronic flash is attached to an interchangeable lens camera having a shutter-priority exposure control. For flash operation, aperture information suitable for electronic flash and the film sensitivity is automatically conveyed to the camera's diaphragm control. Thus the aperture can be automatically adjusted for flash as well as daylight operation.
    Type: Grant
    Filed: September 23, 1975
    Date of Patent: November 28, 1978
    Assignee: Canon Kabushiki Kaisha
    Inventors: Shohei Ohtaki, Tokuichi Tsunekawa, Zenzo Nakamura, Takashi Uchiyama
  • Patent number: 4126877
    Abstract: The present invention relates to a safety device for exposure amount control equipment consisting of a camera and an electronic flash device, including a detecting circuit for detecting the charge voltage of the storage capacitor of the electronic flash device and the voltage of the power source and producing two different electrical signals in accordance with the detected voltages so as to prevent flash light photography with improper exposure amount and a lock member for preventing the movement of a shutter release mechanism of the camera in accordance with the electrical signal produced in the detecting circuit when the detected voltages are lower than a certain determined value.
    Type: Grant
    Filed: April 2, 1976
    Date of Patent: November 21, 1978
    Assignee: Canon Kabushiki Kaisha
    Inventors: Syohei Ohtaki, Zenzo Nakamura, Tokuichi Tsunekawa, Tadashi Ito, Hiroshi Aizawa, Takashi Uchiyama
  • Patent number: 4122467
    Abstract: The present invention relates to a shutter time control circuit of the type in which the shutter time is changed over into a predetermined value for flash light photography in response to a flash charge completion signal from the flash light device. In order to eliminate the shortcoming of the conventional shutter time control circuit of this type, in that when the shutter time is changed over into the value predetermined for flash light photography predetermined shutter time is memorized in a memory capacitor for controlling the shutter time in accordance with the value memorized after the charge completion signal has disappeared.
    Type: Grant
    Filed: November 5, 1976
    Date of Patent: October 24, 1978
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tokuichi Tsunekawa, Zenzo Nakamura, Shohei Ohtaki, Nobuaki Sakurada, Masayuki Suzuki, Takashi Uchiyama
  • Patent number: 4106037
    Abstract: A flash unit is mounted in a lens cap which constitutes an indispensable accessory of the camera.
    Type: Grant
    Filed: December 20, 1976
    Date of Patent: August 8, 1978
    Assignee: Canon Kabushiki Kaisha
    Inventors: Zenzo Nakamura, Goro Hasegawa
  • Patent number: 4100459
    Abstract: An electronic flash apparatus is provided with a display element positioned in the view-finder of a photographic camera so that the operator is immediately aware if the flash tube has been fired in response to the closure of the synchronous switch. The light emitting operation of this display element is controlled by use of a signal generator arranged to be responsive to the occurrence of discharge through the flash tube of the flash apparatus. With this apparatus, therefore, the operator may rely upon the appearance of this display element to insure that the firing is effected by the flash apparatus even when the object-to-camera distance is relatively small.
    Type: Grant
    Filed: March 30, 1976
    Date of Patent: July 11, 1978
    Assignee: Canon Kabushiki Kaisha
    Inventors: Zenzo Nakamura, Syohei Ohtaki, Tokuichi Tsunekawa, Tadashi Ito, Hiroshi Aizawa, Takashi Uchiyama
  • Patent number: 4095242
    Abstract: An adapter matches an electronic flash unit with a single terminal carrying diaphragm and charge data to a camera having separate terminals for these data. A second adapter matches a flash unit having two terminals for diaphragm and charge data to a camera in which these data pass through a single terminal. Circuitry in the adapters combine or separate the data as needed.
    Type: Grant
    Filed: December 7, 1976
    Date of Patent: June 13, 1978
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tokuichi Tsunekawa, Masanori Uchidoi, Zenzo Nakamura, Tetsuya Taguchi, Hiroshi Aizawa, Takashi Uchiyama
  • Patent number: 4095141
    Abstract: The trigger circuit of an electronic flash device includes a pulse transformer connected to a trigger electrode of a flash tube, a capacitor connected to the pulse transformer, a thyristor connected in the discharge path of the capacitor, and a control circuit for the thyristor. This control circuit is provided with a low-voltage trigger means for applying a trigger pulse to said thyristor and further with a synchronous switch connected therein so that the synchronous switch operates with a low voltage.
    Type: Grant
    Filed: February 13, 1976
    Date of Patent: June 13, 1978
    Assignee: Canon Kabushiki Kaisha
    Inventor: Zenzo Nakamura
  • Patent number: RE32425
    Abstract: A flash photographic exposure control system for a camera having an electrically timed shutter is provided with an additional electronic or mechanical timing device in combination with an electronic changeover switch responsive to attainment of the threshold level of the flash unit associated therewith. This is done to switch the camera from an automatic daylight exposure range to an automatic flash exposure range in which a particular timed interval suited for flash photography is made by the timing device which is brought into cooperation with the shutter operating means when the changeover switch is actuated, while the intrinsic timing device for the shutter being cut off from the control means for the shutter.
    Type: Grant
    Filed: December 18, 1984
    Date of Patent: May 26, 1987
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takashi Uchiyama, Yukio Mashimo, Zenzo Nakamura