GB582774A - Improvements in or relating to photographic shutters - Google Patents

Abstract

582,774. Photographic shutters and diaphragms. KODAK, Ltd. May 16, 1944, No. 9385. Convention date, June 3, 1943. [Class 98 (i)] The blades of a photographic shutter open and close the exposure aperture during the setting or tensioning of the shutter and a pivoted lever controlled by the setting member moves the diaphragm leaves so as to cap or cover the aperture during the setting action and is then released to allow the diaphragm leaves to return to a predetermined position under spring action. The diaphragm leaves 10 pivoted to the shutter casing at 11 have a pin-and-slot connection 12, 13 with a diaphragm ring 14. The latter has an arm 15 which is urged towards an adjustable stop pin 16 by a spring 17 which acts on a pivoted lever 18 connected by pin 20 and slot 21 with the diaphragm ring. The pin 16 is carried by an arm 22, the top end of which carries . protuberances which snap into notches on the cover-plate carrying the diaphragm scale. The setting lever 27 is carried by an arcuate slide 28 and a pin 30 thereon engages a slot in the master member. The slide also carries a pivoted latch 34 with a cam-shaped extension 36 which engages a pin 37 on the arm 18 so that when the setting lever is moved to set the shutter, the diaphragm blades are moved across the aperture and remain closed until the pin 37 reaches a notch 39 in the latch and moves to allow the spring 17 to swing the arm 18 in a counter-clockwise direction and return the diaphragm blades to the position determined by the stop 16. In the meantime, the shutter blades have been opened and closed in the setting operation. The shutter mechanism comprises a master member 32 (Fig. 6), carrying two driving pins 41, 42. An arm 43 on the blade ring 44 projects into the path of these pins. The shutter blades 51 are doubleended and symmetrical and carry pins 54 engaging slots 55 in the blade ring 44. The blades are pivoted on a second blade ring 45 which is connected to the ring 44 through rocker arms 46 having pin-and-slot connections with both rings. The pin 41 engages the arm 43 in the setting action and swings the shutter blades across the exposure aperture into the set position. The shutter release trigger 61 carries a latch element 60 engaging a cooperating latch element 59 on the master member and retains the shutter in its set position. It is depressed to release the shutter and the master member then runs down under the action of its spring 40 and the pin 42 strikes the arm 43 causing the blade rings to oscillate and open and close the shutter blades. In the return movement of the slide 28, the spring batch 34 rides idly over the pin 37.