Photographic camera with mechanical, photoelectrically controlled shutter retarding mechanism

摘要

884,735. Photographic cameras. AGFA A.G. May 2, 1958 [May 21, 1957], No. 14157/58. Class 98(1). A camera having a photoelectric exposure meter in which the position of the meter needle is ascertained by an exploring device which automatically sets the shutter retarding mechanism for the correct exposure time, is characterized in that both the retarding mechanism and the exploring device are located in the main camera housing, and not in the shutter housing. The motion is transmitted to the shutter by a Bowden cable. The needle 12 is deflected into a particular position according to the meter reading, and can then be engaged by one of two exploring levers 23, 24 having stepped lower edges. The levers are pivoted at 22, as is also a shutter release lever 25. The pin 22 carries a spiral spring 26 having one end in contact with a lug on lever 25 and its other end in contact with a lug on lever 23. Thus as lever 25 pivots counterclockwise on pressing the camera trigger, it causes, via spring 26, lever 23 to pivot also. Lever 23 takes with it lever 24, since the two are coupled together by a hairpin spring 29. According to the position of needle 12, the stepped lower edge of one or the other of levers 23, 24 engages it, and sets, by means of coupling with a bell-crank lever 38 and pin 39, the appropriate time delay on the shutter retarding mechanism, which is housed (but not shown) between support plates 14, 15. The exploring levers are so designed that lever 23 is applicable for exposure times longer than 1/25th sec., and lever 24 for 1/25th sec. and below. One end of lever 23 has a bent-up end 40 carrying an adjustable screw 41; this operates, via levers 42, 43, a pin 44 which cuts out the escapement of the retarding mechanism and allows the shutter to run down on release. The main driving spring (not shown) is housed between the plates 13, 14, and is tensioned by a gear-and-rack train 19, 20, 21, which may be coupled with a filmadvancing device. The whole assembly is mounted on a supporting arrangement of three generally parallel plates 13, 14, 15, and can form a unitary structure which can be assembled before fitting into the camera, and readily replaced.