GB555467A - Improvements in or relating to photographic shutters - Google Patents

Abstract

555,467. Photographic shutters. KODAK, Ltd (Eastman Kodak Co.). Oct. 31, 1942, No. 15339. [A Specification was laid open to inspection under Sect. 91 of the Acts, June 4, 1943] [Class 98 (i)] In a photographic shutter of the type in which a master member, after tensioning and upon release from the set condition, operates a bladering through a latch, the master-member comprises a pair of co-axially mounted parts, of which one is connected with the setting-lever and is held in set position by the trigger and the other is connected by the latch to the blade ring, the two parts being connected by a lostmotion device so that the first part gathers momentum before commencing to drive the second, whereby a more rapid opening of the blades is achieved. The application of the invention to the shutter described in Specification 491,885 is illustrated. The master member comprises two parts mounted on a stud 6, the first being a disc 8 to which the driving spring (not shown) is attached, and the second a plate 16 to which is pivoted the latch 19 which engages a lug 22 on the blade-operating ring 5. A lug 17 on the plate 16 extends into an arcuate slot 18 in the disc 8, forming the lost-motion connection between the two. The disc 8 is rotated to the set position shown by operation of a setting-arm 11 which slides an arcuate member carrying a rack 9 which engages a pinion 7 secured to the disc. On operation of the latch 13 by the release trigger the disc 8 moves idly and gathers momentum until the other end of the slot strikes the lug 17, causing rapid movement of the plate 16 and hence of the blade ring.