Minolta Camera Kabushiki Kaisha

Takayoshi Miyamoto

Hiroshi Ueda

Masatake Niwa

Takeshi Egawa

Toshio Kobori

Yasuo Yamazaki

A dioptry adjusting mechanism for an eyepiece of a viewfinder for a single lens reflex camera in which the eyepiece includes a negative lens element movable along the optical axis of the view finder for the dioptry adjustment and a stationary positive lens element located at the eye side of the negative lens element, the mechanism including a lever rotatable in response to a manual operation to displace the negative lens element translationally, with a guide member guiding the lens. A manual member for the adjustment may be disposed somewhat remote from the lenses.

Viewfinder dioptry adjusting device for single-lens reflex cameras

In a single lens reflex camera including a camera body provided with a film receptacle, a film transporting mechanism and an operating member for effecting film advancing and shutter cocking; a shutter block in which shutter blades or the like and shutter actuating and controlling mechanism are associated as a unit on a base plate; and a front plate formed with a mount for the camera objective lens and having attached thereto a mirror box which is provided with a reflex mirror, a mirror driving mechanism and a diaphragm driving mechanism, the front plate assembly to which the shutter block is coupled is attached to the camera body, whereby interconnection between the shutter mechanism, the mirror and the diaphragm mechanism is improved.

Camera structure for single lens reflex camera

A motor driven camera has a detachable drive unit, and includes a motor drive circuit which is activated for driving a film wind-up and shutter charge motor on receipt of a signal representative of termination of an exposure. The camera also includes a selector capable of being set at a single frame photographing position as well as at a continuous photographing position, and a control mechanism for preventing generation of the signal with the selector set at the single frame photographing position. A signal generating device is associated with a film wind-up stop mechanism for generating the signal when the stop mechanism is disengaged from a film wind-up and shutter charge mechanism in response to termination of an exposure, disengagement of the stop mechanism being prevented or the signal generating device being deactivated by the control mechanism when the selector is set at its single frame photographing position. The control mechanism is disabled to permit the generation of the signal when a shutter release member is returned from its operative position to its non-operative position.

Motor driven camera having a detachable drive unit

A viewfinder for a single lens reflex camera of the T.T.L. light measurement type, wherein light measurement is apt to be affected by external light entering through an eyepiece, includes a diopter adjusting mechanism and an eyepiece shutter. The eyepiece is divided into at least a movable first optical element and a fixed second optical element. The diopter adjusting mechanism is capable of shifting the first optical element for diopter adjustment within a predetermined space which extends along the viewfinder optical axis and is at least partially common to a space that the eyepiece shutter occupies at an advanced position for blocking the viewfinder optical path. Operation of a manually operable member for shifting the eyepiece shutter toward the advanced positon causes the first optical element to be retracted toward the rear away from the predetermined space prior to the shift of the eyepiece shutter into the advanced position.

Viewfinder for single lens reflex cameras

In a single lens reflex camera including a camera body provided with a film receptacle, a film transporting mechanism and an operating member for effecting film advancing and shutter cocking; a shutter block in which shutter blades or the like and shutter actuating and controlling mechanism are associated as a unit on a base plate; and a front plate formed with a mount for the camera objective lens and having attached thereto a mirror box which is provided with a reflex mirror, a mirror driving mechanism and a diaphragm driving mechanism, the front plate assembly to which the shutter block is coupled is attached to the camera body, whereby interconnection between the shutter mechanism the mirror and the diaphragm mechanism is improved.

A single lens reflex camera includes an electromagnetic release device in which a locking mechanism including an armature is moved to an inoperative position under a spring force to release the locking of a drive member when a solenoid generates a magnetic force to cancel the magnetic attractive force of a permanent magnet, which attractive force attracts the armature to a core, thereby maintaining the locking mechanism in an operative position. The drive member thus released actuates an exposure initiating mechanism of the camera to start exposure operations. In response to the completion of the closing of the shutter, a signal member moves to release a spring loaded resetting member from locking by another locking mechanism. The resetting member thus released resets the first locking mechanism to the operative position against the spring force as well as resets the drive member to a position in which the drive member is capable of being locked again by the first locking mechanism which has been reset to its operative position.

Electromagnetic release device for use in cameras

A camera includes a stroke change-over member which is in first position and a second position respectively when a shutter dial is set for electric exposure control mode and for mechanical exposure control mode. The stroke change-over member, when in the first position, restricts the stroke of the movement of a mechanical release initiating member and, when in the second position, allows the movement of the mechanical release initiating member beyond the restricted stroke, the movement being caused by depression of a shutter button. The camera further includes an electromagnetic release initiating member movable from a first to a second position in response to the depression of the shutter button and a locking member for locking the electromagnetic release initiating member at the first position when the shutter dial is set for mechanical exposure control. The electromagnetic release initiating member allows an electromagnetic release device to release the shutter mechanism when moved a short distance before the movement of the mechanical release initiating member is restricted by the stroke change-over member. The mechanical release initiating member, when moved beyond the restricted stroke, serves to retain the locking of a winding member by another locking member, thereby preventing accidental winding of a film and charging of the shutter mechanism with the shutter button kept depressed as well as allows a mechanical release device to release the shutter mechanism.

Camera with selector for either electromagnetic release or mechanical

A shutter dial releasable locking device for photographic cameras, includes a stationary circular guide member having a number of radially directed stepped portions, a stop member carried by the shutter dial and movable along the circumference of the guide member and biased to engage a stepped portion of the guide member, and a release member biased to project outwardly through a circumferential wall of the shutter dial and adapted to move the stop member in a radial direction of the shutter dial when pressed against a force which biases the release member. When the shutter dial is set in an automatic exposure control position, at a highest shutter speed of manual exposure control or in a mechanical exposure control position, the stop member engages a corresponding stepped portion of the guide member to hold the shutter dial in a position of the selected mode of shutter control.

Growing community of inventors

Sakai, Japan

Takayoshi Miyamoto