Patent GB-1432488-A (GB)
Title: Camera shutter assembly
IPC: G03B9/16
Filed: 1973-06-19
Abstract: 1432488 Camera shutter BERKEY PHOTO Inc 19 June 1973 [11 Oct 1972]. 28955/73 Heading G2A A camera shutter assembly (30) comprises a mounting panel (31) having an opening (32), an apertured first shutter member (34) adjustably mounted on the panel for movement between a first and a second position and, when in the first position having an aperture thereof aligned with the panel opening, and when in the second position having the aperture in non-registered relation with the panel opening whereby the opening is closed by a portion of the first shutter member, the first shutter member being biased to assume the first position, a second shutter member (35) adjustably mounted on the panel and movable to a first position independently of, but subsequent to, the first shutter member having reached its first position whereby the first shutter member aperture is closed by the second shutter member, the second shutter member being biased to assume its first position and being movable to a second position with the first shutter member when the latter is being moved to its second position, the second shutter member when in its second position being out of registration with the panel opening and the portion of the first shutter member closing off the panel opening, a cocking lever (26) adjustably mounted on the panel biased to assume a rest position and manually movable from the rest position to a cocked position independently of the shutter members, a first latch member (38) adjustably mounted on the panel and adapted to operate automatically to retain the cocking lever in the cocked position and movable to a lever release position by the second shutter member upon the latter assuming its first position, a second latch member (40) adjustably mounted on the panel and biased to assume a position whereby the first shutter member is retained in its second position during movement of the  cocking lever to and while disposed in the cocked position, the second latch member subsequent to the cocking lever assuming its cocked position, being adjustable to a release position by a manually actuatable trigger mechanism whereby the first shutter member automatically moves to its first position, a third latch member (43) adjustably mounted on the panel whereby it assumes an interlock position with the second shutter member when the latter is in its second position and retains the second shutter member in its second position during movement of the cocking lever to and while disposed in the cocked position, and time delay means operatively connected to the third latch member for controlling movement of the latter to an unlock position after a finite time interval has elapsed subsequent to the first shutter member assuming its first position. In operation lever (26) is manually moved from rest to cocked position C, the biasing effect of springs 36 and 37 being increased by tongue (26d) being in engagement with spring legs (36a) and (37a). Spring leg (36b) engages nub (34e) and spring 37b engages nub (35c). The trigger mechanism (42) Fig. 10 (not shown) when actuated by depressing trigger button (27) causes lug (53a) to engage finger (40a) thereby causing the second latch member (40) to pivot about post (31c) to release shoulder (34b) from interlocking with notch (40d) thereby releasing the first shutter member (34) so that it can move to its first position A. Upon trigger button (27) being depressed while lever (26) is in position C, lug (53a) is caused to move upwardly and engage finger (40b) thereby moving the second latch member (40) to its first shutter release position and simultaneously, finger (40c) is raised thereby closing switch S2 and switch S3 opens because of the movement of shutter member (34) from B to A which in turn allows the follower (47) to move away relieving closing force on switch S3. Opening switch S3 allows battery voltage to build up across timing capacitor Cl. Closing switch S2 applies battery voltage to photo-sensitive cell PC in series with capacitor Cl and causes capacitor Cl to start charging towards battery voltage. When capacitor C1 charges to the threshold voltage of detector circuit II, the electromagnet (45) becomes de-energized, causing the latch member (43) to be disengaged from notch (35a) allowing shutter member (35) to move to position AA closing aperture (34d) of member (34). Projection (35d) contacts lug (38c) during movement of member (35) to position AA and causes latch member (38) to pivot clockwise so that tongue (26c) is disengaged from slot (38a) and lever (26) moves from position C to position R, due to biasing spring (41), and through engagement of tongue (26e) and shoulder (34b) causes member (34) to move from position A to B which in turn by engagement of flange (34c) and peripheral portion (35b) causes member (35) to move simultaneously from position AA to BB, Fig. 2.