Canon Kabushiki Kaisha

Canon Denshi Kabushiki Kaisha

Yoshihiro Shigeta

Masanori Uchidoi

Hiroshi Yamamoto

Masaharu Kawamura

Yoji Sugiura

Yoichi Tosaka

Ryoichi Yoshikawa

Shosuke Haraguchi

Hiroshi Aizawa

Syuichiro Saito

Fumio Shimada

Michio Senuma

Takehiko Ohniwa

Nobuo Tezuka

Kiyoshi Takahashi

Kuniyoshi Suzaki

Mitsutoshi Ogiso

Masaharau Kawamura

A camera which is provided with a motor for driving a wind-up mechanism to perform film feeding and shutter charging and which is arranged to have photographing actions carried out one after another upon completion of the film feeding and shutter charging, a wind-up device has a switch which is arranged to force the wind-up mechanism into completing the winding up action thereof by means of the motor in response to depression of a rewinding button.

Wind-up device for camera

A single lens reflex camera with a built-in winding motor performing quick return of the mirror and automatic diaphragm in the initial stage of winding operation where the load on the winding motor is very little is disclosed.

Single lens reflex camera

A camera of the type having a winding motor is provided with a timer circuit which, after the lapse of a predetermined length of time, forcibly effects a supply of power to the winding motor when the shutter blades fail to travel in a normal way, and even when a signal corresponding to shutter blade travel completion is not obtained. The winding motor then resets the camera mechanisms which are arranged to perform various operations, such as shutter charging, mirror returning and film feeding, into their respective initial states. This eliminates the possibility of trouble resulting from such a malfunction of the camera that it becomes inoperative halfway through completion of photographing operation.

Safety device for a camera with a winding motor

A camera includes a shutter which is electromagnetically closed at the end of a given exposure time. Circuitry in the camera operates to prevent a prolonged opening of the shutter from occurring when the camera battery voltage drops below a satisfactory operating level during an exposure, wherein the shutter mechanism is forcibly recharged.

Camera

In the disclosed camera, a switchover arrangement automatically shifts from an automatic exposure mode to a flash mode in response to a charge completion signal from a flash device. A line electrically connects a terminal capable of receiving the charge completion signal from the flash unit to the switchover arrangement. A switch connected to the connecting line applies a signal of a value corresponding to the charge completion signal from a signal source in the camera to the switchover arrangement to cause the latter to effect a switchover to the flash mode in response thereto in the same manner as when a charge completion signal is applied thereto.

Camera and automatic exposure control therefor for use with various

In a shutter of the electromagnetic release type arranged to have shutter blades locked by locking members in their charged states and to make an exposure by releasing the shutter blades from the locking members, a first locking member is arranged to lock each of the charged shutter blades while a second locking member is arranged to lock the shutter blade when the shutter blade is released from the first locking member and to have the shutter blade released therefrom by the action of an electromagnet. The releasing torque required for the second locking member is smaller than that of the first locking member.

Electromagnetic release shutter

A hold releasing magnetic device so designed that by controlling the current supply to a magnet the armature is displaced relative to the yoke so as to release a held shutter member wherein the armature and the yoke are supported coaxially with each other on the same shaft on a base plate on which the magnetic device is mounted, with the yoke being securable on the base plate.

Magnetic device

In the disclosed system, a camera of the type which manually presets a diaphragm aperture and particularly for a camera which operates with a computer flash device. For flash operation, the aperture of such a camera must be set at a value suitable for the flash device. A signal representative of an aperture value suitable for the computer flash device and a signal representative of a preset aperture value are compared and, when these two values coincide with each other, the coincidence is displayed by a display device arranged within the view finder to let the photographer know that the camera has been set at an aperture value required for flash photography.

Display device for camera

An automatic exposure control device for a camera capable of permitting flash photography includes an exposure computing portion for natural light photography wherein the computing portion generates an exposure signal corresponding to the brightness of an object and an exposure computing portion for flash photography wherein the computing portion is arranged to generate an exposure signal suitable for a flash photographing operation. An exposure control portion is responsive to one of the exposure signals generated by the natural light photographing exposure computing portion and the flash photographing exposure computing portion. A change-over device applies one of the exposure signals to the exposure control portion. An electromagnetic release device actuates the internal mechanism of the camera wherein the release device produces an electrical signal when it operates. A signal generating device generates a selection signal until the electrical signal is applied from the electromagnetic release device and generates an inhibition signal after application of the electrical signal. A discharge tube emits a flash therefrom an an accumulating portion accumulates light emitting energy for the discharge tube. A detecting device detects the accumulation of the light emitting energy and is arranged to produce a detection signal when the accumulated amount of energy reaches a predetermined value. A triggering device enables the discharge tube to emit a flash in response to the detection signal. The automatic exposure control device performs other functions relative to exposure control.

Exposure control device for camera

A digital system for controlling coordination of the various portions of the camera to operate in selected modes including the automatic and bulb modes is provided with signal forming means comprising a count start switch and a bulb control switch connected in parallel to each other. Where the automatic mode is selected, in a predetermined time interval after the initiation of an actuation of release of the camera, as the both switches are open, the signal forming means produces an actuating signal which is then applied to discriminating means, causing the shutter to operate automatically. Where the bulb mode is selected, no actuating signal is produced even after the termination of duration of the predetermined time interval so that the discriminating means permits the opening of the shutter to continue until the termination of the release actuation.

Coordinating control system for camera

An exposure control device for a camera having a first counter which performs analog-to-digital conversion for a photometric purpose and a second counter for sequence control of each part of the camera. For use of a self-timer, the first and second counters are connected in series with each other to use them in a state of having their steps added together. Upon completion of a self-timer photographing operation, the first and second counters are separated from each other and are brought back into their original conditions.

A device for preventing erroneous operation of a camera is disclosed. The device includes an electromagnet for closing the camera shutter. Current supply apparatus supplies current to the electromagnet. A detection device is employed for detecting whether current from the current supply device has been supplied to the electromagnet. The detection device produces a detection signal when the current is supplied to the electromagnet. A signal generation device has a switch which closes in response to the release operation wherein the signal generation device generates an electrical signal when it receives the detection signal from the detection device. A control device is included for generating a check signal and a release signal. The control device produces the check signal for a predetermined period of time only when it receives the electrical signal from the signal generation device to actuate the detection device. The control device generates the release signal when it receives the detection signal from the detection device. Finally, an electromagnet is included for opening the shutter which is actuated by the release signal from the control device so as to operate only when the current passage to the shutter control electromagnet is detected.

A safety device for preventing non exposure of film in a camera having a count switch which is normally closed prior to shutter release operation, the switch being opened after the shutter release operation begins to enable a timing circuit to start operating. In a preferred embodiment, the device includes a NOR gate having an input connected to one side of the count switch, and its output connected to the set terminal of a flip-flop which enables the shutter release operation. Another input of the NOR gate is connected to a differentiation circuit which provides an output signal when the shutter release button on the camera is actuated. This circuit arrangement operates so that the flip-flop is not set if the count switch is accidently in an open state when the release button is actuated. The shutter release operation is thereby prevented until the count switch is restored to working order.

Safety device for camera

A system for controlling development conditions under which an exposed film strip is processed with a compact multi-purpose film handling cartridge. The film cartridge which is adapted to be mounted in a motion picture camera and projector employing the system of the invention and including motor drive means contains a strip of film, a processing station, film advance means engaging said drive means when the cartridge is mounted in said camera or projector, and an applicator containing development chemicals positioned in said processing station to be brought into operable relationship with the film strip when said processing station is rendered operable, thereby they are expressed onto the film strip from the applicator while said film strip is being advanced. In order to optimize the processing of the exposed film strip regardless of deviation of the temperature of the development chemicals from a desired predetermined level, the system includes means located in close proximity to the applicator for detecting the ambient temperature thereof, a first motor control means cooperating with said temperature detecting means to control the speed of said motor in accordance with the detected temperature, and a second motor control means for maintaining a constant rate of travel of the film strip advanced by said film advance means across the processing station, said first and second motor control means being associated with each other for processing the exposed film strip in optimization as well as in uniformity along the length of the film strip.

Processing condition control system for a multi-purpose film handling

A system is disclosed for retrieving a film having video information recorded thereupon in synchronism with a magnetic tape having audio information recorded thereupon and for synchronizing the sound with the picture after retrieval. Address signals are recorded upon both the film and the tape. The system comprises detectors for address signals recorded upon the film and the tape, a computer including a keyboard for retrieving a desired address, comparators for comparing the outputs of the detectors with the output of the computer, and means for transporting the film and tape in response to the outputs of the comparators. Control signals are recorded upon both the tape and film for synchronizing the sound with the picture. When the control signal recorded upon the film is detected, the still picture is projected and when the control signal recorded on the tape is detected the motion picture is projected.

Growing community of inventors

Tokyo, Japan

Yoshihiro Shigeta