Device for correcting the open aperture ratio of interchangeable lenses in a camera self-containing a ttl exposure meter

Claim 2

In a single lens reflex camera having an interchangeable lens and a built-in exposure meter with a photo-sensitive element responsive to the light through the maximum aperture of the lens, the improvement comprising: a. means for mounting said lens to the camera body; b. a lens barrel provided in the interchangeable lens and having an abutment at the common position thereof; c. a lens stop adjusting ring provided in said lens; d. an exposure control member operatively associated with said exposure meter, rotatably mounted on the camera body and biased to a rest position; e. means for interconnecting said stop adjusting ring with said exposure control member; said interconnecting means being provided on said stop ring, spaced from said abutment by a distance according to the maximum aperture ratio of said lens when said stop ring is set to the maximum aperture position of said lens, movable to an extended position for preventing the mounting of said lens to said camera body and to a retracted position for allowing said mounting and biased toward its extended position; f. means for preventing the movement of said interconnecting means from its extended position to its retracted position except when the said stop ring is set to the maximum aperture position of said lens and for allowing said movement and connecting said lens barrel with said stop ring in co-operation with said interconnecting means only when said stop adjusting rings is set to the maximum aperture position of said lens; g. an auxiliary member rotatably independently of the control member mounted on the camera body, biased to a rest position and provided with a surface on which said interconnecting means slides during mounting movement of said lens, said surface being formed with a hole engageable with said interconnecting means during the mounting of said lens, said exposure control member being formed with a second abutment engageable with said abutment during the mounting of said lens to cause the relative displacement between said exposure control member and said auxiliary member according to the maximum aperture ratio of said lens until said interconnecting means is engaged with said hole in said surface; and h. means for connecting said exposure control member with said stop adjusting ring in cooperation with said interconnecting means through said hole when said relative displacement is completed.

Claim 3

The apparatus as defined in claim 1 wherein said preventing means comprises a flange having a concave portion for allowing the movement of said interconnecting means from its extended position to its retracted position when said aperture adjusting ring is set to the maximum aperture position of said lens, and wherein said interconnecting means comprises an interconnecting pin having a flange portion engageable with said concave portion to connect said aperture adjusting ring with said lens barrel in its retracted position and a neck portion slidable on said flange of said preventing means in its extended position.

Claim 4

The apparatus as defined in claim 1, wherein said connecting means is a row of apertures provided on said exposure control member, each aperture thereof being arranged to be aligned with said hole in said auxiliary member for connecting said exposure control member with said stop adjusting ring in cooperation with said interconnecting means through said hole when said relative displacement between said exposure control member and said auxiliary member is completed.

Claim 5

The apparatus as defined in claim 1 and further comprising means for biasing said exposure control member toward its rest position.

Claim 6

The apparatus as defined in claim 4 wherein said biasing means comprises a first member being biased toward its rest position, a second member for interlocking said exposure control member with said first member to bias said control member toward its rest position, and a cam member provided on said camera body to engage with said second member when the mounting of said lens to said camera is completed thereby to set free said exposure control member from the biasing of said first member.

Claim 7

In a single lens reflex camera having an interchangeable lens and a built-in exposure meter with a photo-sensitive element responsive to the light through the maximum aperture of the lens, the improvement comprising: a. means for mounting said lens to the camera body; b. a lens barrel provided in said interchangeable lens and having an abutment at the common position thereof; c. a lens stop adjusting ring provided in said lens; d. an exposure control member operatively associated with said exposure meter rotatably mounted on said camera body and biased to a rest position; e. an auxiliary member independently rotatable of said control member, said auxiliary member being mounted on said camera body and biased to a rest position; f. means for interconnecting said lens stop adjusting ring with said auxiliary member, said interconnecting means being provided on said stop adjusting ring, spaced from said abutment by a distance according to the maximum aperture ratio of said lens when the said ring is set to the maximum aperture position of said lens, movable to an extended position for preventing the mounting of said lens to said camera body and to a retracted position for allowing said mounting and biased toward its extended position; g. means for preventing the movement of said interconnecting means from its extended position to its retracted position except when said stop ring is set to the maximum aperture position of said lens and for allowing said movement and connecting said lens barrel with said stop adjusting ring in cooperation with said interconnecting means only when said stop ring is set to the maximum aperture position of said lens; h. means for locking said exposure control member at the rest position thereof and having an engaging portion engageable with the abutment on said lens barrel for releasing said control member from the locking position of said locking means, said auxiliary member having a surface on which said interconnecting means slides during the mounting of said lens, said surface being formed with a hole engageable with said interconnecting means during the mounting of said lens to cause relative displacement between said cOntrol member and said auxiliary member until said control member is released; i. means for connecting said exposure control member with said auxiliary member when relative displacement is completed; and j. means for latching said interconnecting means at the retracted position thereof until mounting movement of said lens is completed.

Claim 8

In a single lens reflex camera having an interchangeable lens and a built-in exposure meter with a photo-sensitive element responsive to the light through the maximum aperture of the lens, the improvement comprising: a. means for mounting said lens to the camera body; b. a lens barrel provided in said interchangeable lens and having an abutment at the common position thereof; c. a lens stop adjusting ring provided in said lens; d. an exposure control member operatively associated with said exposure meter rotatably mounted on said camera body and biased to a rest position; e. an auxiliary member independently rotatable of said control member, said auxiliary member being mounted on said camera body and biased to a rest position; f. means for interconnecting said lens stop adjusting ring with said auxiliary member, said interconnecting means being provided on said stop adjusting ring, spaced from said abutment by a distance according to the maximum aperture ratio of said lens when the said ring is set to the maximum aperture position of said lens, movable to an extended position for preventing the mounting of said lens to said camera body and to a retracted position for allowing said mounting and biased toward its extended position; g. means for preventing the movement of said interconnecting means from its extended position to its retracted position except when said stop ring is set to the maximum aperture position of said lens and for allowing said movement and connecting said lens barrel with said stop adjusting ring in cooperation with said interconnecting means only when said stop ring is set to the maximum aperture position of said lens; h. means for locking said exposure control member at the rest position thereof and having an engaging portion engageable with the abutment on said lens barrel for releasing said control member from the locking position of said locking means, said auxiliary member having a surface on which said interconnecting means slides during the mounting of said lens, said surface being formed with a hole engageable with said interconnecting means during the mounting of said lens to cause relative displacement between said cOntrol member and said auxiliary member until said control member is released; i. means for connecting said exposure control member with said auxiliary member when relative displacement is completed; and j. means for latching said interconnecting means at the retracted position thereof until mounting movement of said lens is completed.

Claim 9

The apparatus as defined in claim 6 wherein said preventing means comprises a flange having a concave portion for allowing the movement of said interconnecting means from its extended position to its retracted position when said aperture adjusting ring is set to the maximum aperture position of said lens and wherein said interconnecting means comprises an interconnecting pin having a flange portion engageable with said concave portion to connect said aperture adjusting ring with said lens barrel in its retracted position and a neck portion slidable on said flange of said preventing means in its extended position.

Claim 10

The apparatus as defined in claim 6 wherein said latching means comprises a latching member, a second member and a cam, said latching member rotatably mounted on said lens barrel and having a first member engageable with said interconnecting means to latch said interconnecting means at the retracted position, said latching means being biased in a direction in which said first member is disengaged from said interconnecting means; said second member secured to said latching member and extending toward said camera body, and said cam being provided on said camera body for controlling said latching member to engage said first member with said interconnecting means until the mounting movement of said lens to said camera body is completed.

Claim 11

The apparatus as defined in claim 6 wherein said connecting means comprises a pawl member rotatably mounted on said exposure control member and biased in the direction in which said pawl member engages said auxiliary member, and wherein a row of notches are provided on said auxiliary member, each notch thereof being arranged to be engaged by said pawl member for connecting said control member with said auxiliary member when said relative displacement between said exposure control member and said auxiliary member according to the maximum aperture ratio of said lens is completed.