GB1043814A - Camera shutter - Google Patents

Abstract

1,043,814. Photographic shutters. HATTORI TOKEITEN KABUSHIKI KAISHA. July 3, 1964 [July 3, 1963; March 25, 1964; June 5, 1964], No. 27613/64. Heading G2A. The blades of a photographic shutter also constitute the leaves of the iris diaphragm. The blades are preferably controlled by an escapement to move at a constant speed throughout the duration of the exposure, which is timed automatically by an electro-optical delay circuit (Fig. 5, not shown), and are closed rapidly at its end by electro-magnetic means. As shown, the shutter has two blades 1 pivoted at B and driven by a pin-and-slot connection with an opening member 3. The shutter is cocked by raising lever 15, which is pivoted at 13 and has projections 16 and 15a. The projections rotate members 10 and 4 to positions in which they are retained by pawls 17 and 6 respectively. On turning release trigger 29, pin 30 allows contacts 101 and 104 to close and operate a warning lamp if there is insufficient light for an automatically controlled exposure. Further movement of trigger 29 rotates pawl 17 to release member 10 whose initial rotation releases lever 24 from pin 16c to close contacts 100,103 and open contacts 100, 102. The delay circuit is thus brought into operation immediately before the escapement controlled rotation of member 10 allows pin 8 of opening member 3 to slide on cam profile 10b of member 10. The opening member 3 continues to rotate and open blades 1 until the delay circuit energizes electro-magnet 50. The exposure is ended by armature 52 retracting pawl 6 and allowing closure member 4 to engage projection 11 under spring action and close blades 1. For a manually controlled exposure at full aperture, the escapement is disconnected so that the rotation of member 10 is unrestricted. In another form, (Fig. 8, not shown) a multibladed shutter is controlled by blade rings operating as opening and closure members.