Exposure controls for motion picture cameras

Claim 2

In a motion picture camera, adjustable diaphragm means, drive means operatively connected to said adjustable diaphragm means for adjusting the latter, light-responsive means operatively connected with said drive means for actuating the latter to adjust said diaphragm means in response to changes in lighting conditions, rotary shutter means formed with an opening through which film is exposed at each revolution of said shutter means, adjusting means operatively connected with said rotary shutter means for adjusting the size of said opening thereof, and transmission means operatively connected on the one hand with said drive means and on the other hand with said adjusting means for actuating the latter to adjust said opening of said shutter means when said drive means is actuated to adjust said diaphragm means.

Claim 3

The combination of claim 1 and wherein a clutch means is included in said transmission means and has an engaged position interconnecting a part of said transmission means which extends from said drive means with a part of said transmission means which extends to said adjusting means, and manually operable means operatively connected with said clutch means for placing the latter in a disengaged position separating said parts of said transmission means from each other and rendering the part of said transmission means which extends to said adjusting means manually operable for manual adjustment of said opening of said rotary shutter means.

Claim 4

The combination of claim 1 and wherein a compensating means is situated in the path of light travelling to said light-responsive means for altering the amount of light received thereby, said transmission means being operatively connected with said compensating means for actuating the latter simultaneously with said adjustable diaphragm means and said adjusting means to alter the amount of light received by said light-responsive means in response to operation of said drive means.

Claim 5

The combination of claim 1 and wherein said rotary shutter means includes a rotary shutter formed at its periphery with an arcuate shutter opening extending through a given angle, said adjusting means including an adjusting plate coaxial with said rotary shutter and turnable with respect thereto for covering said opening to a given extent for adjusting the size of the shutter opening, a pair of telescoped tubes coaxial with said shutter and adjusting plate and respectively fixed thereto, one of said tubes being formed with an axial slot and the other of said tubes being formed with a helical slot extending across said axial slot, a transverse pin extending through both of said slots, and a plunger carrying said pin and axially movable within the inner one of said telescoped tubes for displacing said pin with respect to said slots for turning said adjusting plate with respect to said shutter, said transmission means being operatively connected with said pin for axially displacing the latter to adjust the angular position of said shutter and adjusting plate one with respect to the other.

Claim 6

The combination of claim 4 and wherein a rotating means is operatively connected with the outer one of said telescoped tubes for rotating both of said tubes together with said shutter and adjusting plate as a unit, and said plunger and transverse pin also rotating together with said telescoped tubes and said shutter and adjusting plate, said transmission means including a connecting means operatively connected with said plunger for controlling the axial position of the latter while freeing said plunger for free rotary movement with respect to said transmission means.

Claim 7

The combination of claim 5 and wherein said connecting means includes a portion of said plunger which is formed with an annular groove and an output member of said transmission means having a portion situated in said groove so that said plunger will move axially in response to movement of said portion of said output member axially of said plunger whilE the latter is free to rotate with respect to said portion of said output member.

Claim 8

The combination of claim 6 and wherein said output member of said transmission means is in the form of a slide block having at its periphery a flange extending into said groove of said plunger and thus forming said portion of said output member of said transmission means, a rotary tube on which said slide block is axially slidable, said rotary tube extending parallel to said plunger, an inner member extending along the interior of said rotary tube and supporting the latter for rotation, said inner member and rotary tube forming a pair of members one of which is formed with an axial cutout and the other of which is formed with a helical cutout extending across the axial cutout, said slide block carrying a transverse pin extending into both of said cutouts so that in response to rotary movement of said rotary tube said slide block will be axially shifted to transmit axial movement to said plunger for determining the angular position of said adjusting plate and shutter one with respect to the other, said transmission means including a driven gear fixed to said rotary tube and a drive gear meshing with said driven gear for rotating the latter and said rotary tube therewith when said drive means operates.

Claim 9

The combination of claim 7 and wherein said transmission means includes a clutch means for transmitting rotation from said drive means to said driving gear, said clutch means including a pair of clutch members one of which is fixed with said driving gear and the other of which is operatively connected with said drive means to rotate whenever said drive means operates, said clutch means including a motion-transmitting element for transmitting motion between said clutch members when said clutch means is in an engaged position, and manually operable means operatively connected with said one clutch member for displacing the latter to a disengaged position with respect to said other clutch member where said motion-transmitting member no longer transmits motion between said clutch members, said manually operable means being operatively connected with said driving gear so that the latter may be rotated manually when said clutch means is in its disengaged position, thus permitting said adjusting plate and shutter to be manually adjusted one with respect to the other when said clutch means is in its disengaged position.

Claim 10

The combination of claim 1 and wherein said drive means includes a servomotor electrically connected with said light-responsive means for being controlled by the latter to operate said drive means.

Claim 11

The combination of claim 1 and wherein the camera includes an objective through which light travels to the interior of the camera, and light-directing means receiving light from said objective except when said opening of said shutter permits light to travel from the objective to film which is to be exposed and for directing the light after it has travelled through said objective to said light-responsive means for actuating the latter.

Claim 12

The combination of claim 1 and wherein said transmission means is operatively connected with said adjustable means for providing at said rotary shutter means exposure times which have a predetermined relationship with respect to the F-number settings of said diaphragm means.

Claim 13

The combination of claim 11 and wherein said relationship provides an exposure time of 1/125 sec. at an F-number setting of 16.