Automatic exposure control device for a photographic camera

Claim 2

An automatic exposure control device for a photographic camera having an objective lens and a diaphragm, comprising: a light receiving element receiving scene light passing through the objective lens and an aperture of the diaphragm; a shutter for giving exposure according to set shutter speeds; a release member for initiating exposure operation of said shutter; a working member displaceable from its charged position to its position of rest in relation to the operation of said release member; a diaphragm adjusting member interlocking with said working member for opening the diaphragm aperture fully when said working member is in said charged position and for reducing down said diaphragm aperture with the displacement of said working member to said rest position; stopper means engageable with said working member for stopping the displacement of the same; an exposure controlling circuit provided with a detecting circuit including said light receiving element and generatable output as a function of light intensity incident on the light receiving element, the sensitivity of the film used and the set speed of said shutter; and electromagnetic means responsive to the output of said exposure controlling circuit to actuate said stopper means, whereby said diaphragm aperture is stopped at a size according to said scene light.

Claim 3

A photographic camera as set forth in claim 1, further comprising a camera body, including said working member and wherein said objective lens is detachable and exhangeable and includes said diaphragm adjusting member which is interlocked with said working member in said camera body when said exchangeable objective lens is attached to said camera body.

Claim 4

A photographic camera as set forth in claim 1, wherein said electromagnetic means includes an electromagnet which is energized with the generation of the output in said exposure controlling circuit.

Claim 5

A photographic camera as set forth in claim 1, wherein said electromagnetic means includes an electromagnet which is de-energized with the generation of the output in said exposure controlling circuit.

Claim 6

A photographic camera as set forth in claim 1, wherein said working member is provided with a toothed portion and said stopper means is provided with a pawl engageable with said toothed portion of said working member.

Claim 7

A photographic camera as set forth in claim 5 wherein the camera is a single lens reflex camera having a view finder and comprising: a shutter having a front curtain movable from a cocked position to a rest position for initiating exposure; a rear curtain movable from a cocked position to a rest position for terminating said exposure; a shutter speed setting means for controlling the time interval at which said front curtain and said rear curtain is actuated to be driven; a reflecting mirror fixedly mounted on an axle for movement between a viewing position for reflecting the scene light passed through the lens and the diaphragm aperture to the view finder and a picture-taking position; said light receiving element receiving said scene light being arranged within an optical path of said scene light reflected by said reflecting mirror at the viewing position; a camera body; a switch of said controlling circuit being closed with the release operation of said release member; a retaining member for retaining said working member at its charged position thereof and for releasing said retention through said release operation of said release member after the closing of said switch is terminated; a locking member for retaining said retaining member in its released position and for moving said retaining member into and out of engagement with said stopper means attracted to said electromagnetic means; a camera release lever operatively mounted on said camera body for actuation by said release member; a mirror lever rotatably mounted on said mirror axle for rotating said mirror from the viewing position to the picture-taking position in relation to the release working of said camera release lever actuated during the last stage of the stroke of said release member during said said release operation; a mirror return lever fixedly mounted on said mirror axle and cooperating with said mirror lever for returning said mirror from said picture-taking position to said viewing position; a connecting lever operatively mounted on said camera body for engagement with said mirror return lever and said retaining member; and means cooperating with said rear curtain for releasing the engagement of said connecting lever with said mirror return lever in relation to the completion of the driving of said return lever from the cocked position to the rest position.

Claim 8

A photographic camera as set forth in claim 6 wherein said connecting lever, when in engagement with said mirror return lever, engages with said retaining member which engages with said stopper means, said pawl of said stopper means engaging with said toothed portion of said working member thereby retaining said retaining member; and wherein said connecting member, when moved out of engagement with said mirror return lever in relation with the completion of the rear curtain driving, rotates in the position where said stopper means is brought into contact with said electromagnetic means, thereby breaking the engagement of said locking member with said retaining member.

Claim 9

An automatic exposure control device for a photographic camera having an objective lens and a diaphragm, comprising: a shutter having a front curtain movable from a cocked position to a rest position for initiating exposure; a rear curtain movable from a cocked position to a rest position for terminating said exposure; a shutter speed setting member controlling the time interval at which said front curtain and said rear curtain is actuated to be driven; a light receiving element receiving a scene light passing through the objective lens and an aperture of the diaphragm; a view finder; a release member for initiating exposure operation of said shutter; a working member displaceable from its charged position to its position of rest in relation to the operation of said release member; a reflecting mirror fixedly mounted on an axle for movement between a viewing position for reflecting the scene light passed through the objective lens and the diaphragm aperture to the view finder and a picture-taking position; said light receiving element for receiving said scene light being arranged within an optical path of said scene light reflected by said reflecting mirror at the viewing position; said working member having a toothed portion and means biasing said working member for displacement while releasing the retention of said retaining member; stopper means provided with a pawl engageable with said toothed portion for stopping the displacement of said work member; an exposure controlling circuit provided with a detecting circuit including said light receiving element and generatable output as a function of light intensity incident on the light receiving element, the sensitivity of the film used and the set speed of said shutter; electromagnetic means responsive to the output of said exposure controlling circuit to actuate said stopper means, whereby said diaphragm aperture is stopped at a size according to said scene light; said exposure controlling circuIt including a switch which is closed at a first stage of a stroke of said release member during its release operation; a retaining member for retaining said working member at its charged position thereof and for releasing said retention through said release operation of said release member at a second stage of its stroke; a mirror lever mounted for rotation on said mirror axle and cooperating with said stopper means so as to be released thereby when said pawl of said stopper means is brought into engagement with said toothed portion and thereby driving said movable reflecting mirror from said viewing position to said picture-taking position; a mirror return lever fixedly mounted on said mirror axle and cooperating with said mirror lever for returning said mirror from said picture-taking position to said viewing position; and a shutter release lever mounted for cooperation with said mirror lever for releasing the driving of said front curtain from the cocked position to the rest position with the releasing of said mirror lever.

Claim 10

An automatic exposure control device for a photographic camera having an objective lens and a diaphragm, comprising: a shutter having a front curtain movable from a cocked position to a rest position for initiating exposure; a rear curtain movable from a cocked position to a rest position for terminating said exposure; a shutter speed setting member controlling the time interval at which said front curtain and said rear curtain is actuated to be driven; a light receiving element receiving a scene light passing through the objective lens and an aperture of the diaphragm; a view finder; a release member for initiating exposure operation of said shutter; a working member displaceable from its charged position to its position of rest in relation to the operation of said release member; a reflecting mirror fixedly mounted on an axle for movement between a viewing position for reflecting the scene light passed through the objective lens and the diaphragm aperture to the view finder and a picture-taking position; said light receiving element for receiving said scene light being arranged within an optical path of said scene light reflected by said reflecting mirror at the viewing position; said working member having a toothed portion and means biasing said working member for displacement while releasing the retention of said retaining member; stopper means provided with a pawl engageable with said toothed portion for stopping the displacement of said work member; an exposure controlling circuit provided with a detecting circuit including said light receiving element and generatable output as a function of light intensity incident on the light receiving element, the sensitivity of the film used and the set speed of said shutter; electromagnetic means responsive to the output of said exposure controlling circuit to actuate said stopper means, whereby said diaphragm aperture is stopped at a size according to said scene light; said exposure controlling circuIt including a switch which is closed at a first stage of a stroke of said release member during its release operation; a retaining member for retaining said working member at its charged position thereof and for releasing said retention through said release operation of said release member at a second stage of its stroke; a mirror lever mounted for rotation on said mirror axle and cooperating with said stopper means so as to be released thereby when said pawl of said stopper means is brought into engagement with said toothed portion and thereby driving said movable reflecting mirror from said viewing position to said picture-taking position; a mirror return lever fixedly mounted on said mirror axle and cooperating with said mirror lever for returning said mirror from said picture-taking position to said viewing position; and a shutter release lever mounted for cooperation with said mirror lever for releasing the driving of said front curtain from the cocked position to the rest position with the releasing of said mirror lever.

Claim 11

An automatic exposure control device for a photographic camera having an objective lens and diaphragm, comprising: a camera body; a curtain shutter having a front curtain movable from a cocked position to a rest position for initiating exposure, a rear curtain movable from a cocked position to a rest position for terminating said exposure; a light receiving element receiving a scene light passing through the objective lens and an aperture of the diaphragm; a view finder; a shutter speed setting member for controlling the time interval at which said front curtain and said rear curtain is actuated to be driven; a reflecting mirror fixedly mounted on an axle for movement between a viewing position for reflecting the scene light passed through the objective lens and the diaphragm aperture to the view finder and the picture-taking position for passing said scene light toward a film; said light receiving element being positioned between said reflecting mirror and said shutter curtains and movable between a first position within the optical path of the scene light when said reflecting mirror is in said picture-taking position for receiving said scene light and a second position withdrawn from said optical path; a release member for initiating exposure operation of said curtain shutter; a driving member operatively mounted on said camera body and being retained by said release member to be released during the release operation of said release member; a mirror lever fixedly mounted on said mirror axle and engaging with said driving member; a working member provided with a toothed portion and being urged by a spring means to be driven from a charged position to a rest position; a retaining member operatively mounted on said camera body and being engageable with said driving member for retaining said working member at said charged position thereof against said spring means; governor means operatively mounted on said camera body and being provided with a gear for engaging with said toothed portion; a diaphragm adjusting member interlocking with said working member for opening the diaphragm aperture fully when said working member is retained at the charged position and for cutting down said diaphragm aperture with the displacement of said working member from its charged position to its rest position; stopper means provided with a pawl engageable with said governor means for stopping the displacement of said working member; an exposure controlling circuit provided with a detecting circuit including said light receiving element and generatable output as a function of light intensity incident on the light receiving element, the sensitivity of the film used and the set speed of said shutter; electromagnetic means responsive to the output of said exposure controlling circuit to actuate said stopper means, whereby said diaphragm aperture is stopped at a size acCording to said scene light; and means on said light receiving element engaging with said stopper means for driving said light receiving element from the first position to the second position with the actuation of said stopper means.

Claim 12

An automatic exposure control device for a photographic camera having an objective lens and diaphragm, comprising: a camera body; a curtain shutter having a front curtain movable from a cocked position to a rest position for initiating exposure, a rear curtain movable from a cocked position to a rest position for terminating said exposure; a light receiving element receiving a scene light passing through the objective lens and an aperture of the diaphragm; a view finder; a shutter speed setting member for controlling the time interval at which said front curtain and said rear curtain is actuated to be driven; a reflecting mirror fixedly mounted on an axle for movement between a viewing position for reflecting the scene light passed through the objective lens and the diaphragm aperture to the view finder and the picture-taking position for passing said scene light toward a film; said light receiving element being positioned between said reflecting mirror and said shutter curtains and movable between a first position within the optical path of the scene light when said reflecting mirror is in said picture-taking position for receiving said scene light and a second position withdrawn from said optical path; a release member for initiating exposure operation of said curtain shutter; a driving member operatively mounted on said camera body and being retained by said release member to be released during the release operation of said release member; a mirror lever fixedly mounted on said mirror axle and engaging with said driving member; a working member provided with a toothed portion and being urged by a spring means to be driven from a charged position to a rest position; a retaining member operatively mounted on said camera body and being engageable with said driving member for retaining said working member at said charged position thereof against said spring means; governor means operatively mounted on said camera body and being provided with a gear for engaging with said toothed portion; a diaphragm adjusting member interlocking with said working member for opening the diaphragm aperture fully when said working member is retained at the charged position and for cutting down said diaphragm aperture with the displacement of said working member from its charged position to its rest position; stopper means provided with a pawl engageable with said governor means for stopping the displacement of said working member; an exposure controlling circuit provided with a detecting circuit including said light receiving element and generatable output as a function of light intensity incident on the light receiving element, the sensitivity of the film used and the set speed of said shutter; electromagnetic means responsive to the output of said exposure controlling circuit to actuate said stopper means, whereby said diaphragm aperture is stopped at a size acCording to said scene light; and means on said light receiving element engaging with said stopper means for driving said light receiving element from the first position to the second position with the actuation of said stopper means.