Patent GB-934738-A (GB)
Title: Improvements in or relating to motion picture cameras
IPC: G03B19/18
Filed: 1961-09-11
Abstract: 934,738. Kinematograph cameras. EASTMAN KODAK CO. Sept. 11, 1961 [Sept. 12, 1960], No. 32466/61. Class 97 (1). A motion-picture camera comprises a shutter, means for driving said shutter to make an exposure, and control means for said shutter and drive means; said control means including a latch for releasably holding said shutter against exposure-making movement and operating means for said latch, said operating means having an in-operative position in which the latch holds the shutter against movement, and being manually movable into three operating positions, in the first of which the latch is held disengaged so that the shutter makes successive exposures for so long as the operating means is manually held in the first position, in the second of which the latch is held disengaged and a lock holds the operating means so that the shutter makes successive exposures until the lock is disengaged, and in the third of which the latch is caused to be disengaged long enough for the shutter to make on exposure only regardless of the length of time the operating means is in said third position; said control means also having means operable to prevent movement of the operating means into any of the operating positions. As shown, a motion-picture camera comprises a shutter disc 8 mounted on a shaft 12 and coupled to an electric drive motor (not shown) by way of a slip clutch (not shown). A disc cam 14 also mounted on the shaft 12 is provided with a notch 15 which is normally engaged by the upper end of a pivoted latch-lever 16 under loading of a spring 21. In the position shown (said second position), the lever 16 is pivoted out of engagement with said notch, thereby permitting continuous operation of the camera by a pivoted operating lever 22 which has an end 24 for engaging with an end 25 of the lever 16 and is held in the position shown against loading of a spring 27 by an operating button 29 slidable in the shutter casing 35. Lever 22 also has a projection 57 which deflects a sprung contact 52 into engagement with a contact 55 for energizing the drive motor for the shutter disc 8. In this continuous operating position, a sprung catch 42 (cf. also Fig. 5, not shown) engages behind a shoulder of the casing 35 for releasably holding the button 29 in its depressed position. If a plate 38 is rotated to bring a mark " R " uppermost, then the camera operates in exactly the same way as described above, on depression of the button 29, but the extent to which this button 29 can be depressed (to said first position) is reduced slightly so that the catch 42 cannot be operated. If it is desired to take single frame exposures, then the plate 38 is rotated so that a mark " S " is uppermost. This allows the button 29 to be depressed the greatest distance (to said third position), so that, on depression of button 29, end 25 slips off end 24 and the lever 16 pivots back towards the disc 14 under its spring loading. Immediate return of its upper end into the notch 10 is, however, prevented by an upstanding finger 13 of a spring disc 11, said return being delayed until the disc 14 and connected shutter blade have been driven through one revolution. In this single exposure position of the plate 38, the contact 55 is lowered by an eccentric 48 so as to delay energizing of said drive motor until members 16, 13 are in engagement. End 25 of lever 16 is constructed in a flexible manner so as to facilitate return of the lever 22 to its rest position without again disengaging the latch. A final setting position L of the plate 38 effectively locks the button 29 and prevents any kind of operation of the camera.