Patent GB-1019722-A (GB)
Title: Photographic shutter
IPC: G03B9/22
Filed: 1964-03-09
Abstract: 1,019,722. Photographic camera shutters. CARL ZEISS-STIFTUNG, [trading as Carl Zeiss] and COMPUR-WERK G.m.b.H., [together trading as COMPURWERT G.m.b.H. ). March 9,1964 [April 26, 1963], No. 9807/64. Heading G2A. In a photographic shutter having an opening device which actuates the shutter blades to open and close for an interim inspection, the said device has means connecting it to the exposure release so that it may be operated by manipulation of the exposure release. The shutter blades 12 each have a pin 12a engaging in a slot 44a in a ring 44, and a slot in which engages a pin 14a of a ring 14. Ring 14 is the blade-opening ring, and is driven from a main driving member 16, tensioned against its driving spring 24 by a cocking lever 22 through a pinion 20. Member 16 is held in the tensioned position by an arm 26a of a locking lever 26. When arm 26a is pivoted clockwise, member 16 is released, to impart, as it runs down, via a link 18 and a lug 14b, a clockwise and then anticlockwise movement to ring 14, so opening and then closing the shutter blades. The exposure time is set by a retarding mechanism (not shown) associated with member 16. The release is actuated by anticlockwise movement of the release lever 30, which moves to the left a transfer lever 34 to which it is linked at 30b. A pin 34a<SP>1</SP> at the end of lever 34 is engaged behind a lug 26b<SP>1</SP> at the end of arm 26b of lever 26, so pivoting it to release member 16. Opening of the shutter for interim inspection is controlled by ring 44, and operated by lever 48b. When this turned clockwise, a pin 44b on ring 44 enters a slot 48c in the lever, and is carried round into the position of Fig. 3 (not shown). Thus ring 44 is turned, to open the shutter. During this movement, the pin 44b comes into engagement with the surface 56b of a control lever 56 mounted on the same pivot 48a as lever 48b. This is pivoted clockwise and engages in turn, by means of a pin 56a, the end of transfer lever 34, thus disengaging its other end 34a<SP>1</SP> from locking lever 26. The driving member 16, therefore, in this position, cannot be unlatched to run down. A pin 52a on a catch 52 locks behind a corner 48f of lever 48b to hold this position. To close the shutter after inspection, lever 48b is given a slight anticlockwise movement, which disengages the corner 48f from the catch pin 52a, and under the action of spring 46, which connects together rings 14 and 44, ring 44 returns to the Fig. 2 position, together with lever 48b and control lever 56. This allows transfer lever 34 to reengage with locking lever 26, so that the release lever 30 is once more positively connected to the member 16 for making an exposure. An alternative way of closing the shutter after inspection is by moving the release lever 30 anticlockwise, which moves the transfer lever to the left. This is slightly tilted by pin 56a so that the concave end 34b<SP>1</SP> of the lever pushes against the catch pin 52a, releasing the corner 48f of lever 48b, thus allowing all the parts to return to the Fig. 2 position as before. A second movement of lever 30 now effects the normal release. For a T- exposure of more than eight seconds the driving member is not used. A time control 60 is turned anticlockwise until the pin 56a on control lever 56 rides over it (Fig. 5, not shown). This disconnects the retarding mechanism, and also moves the transfer lever 34 to disengage it from the locking lever 26. To open the shutter for an interim inspection in this T-position, either lever 48b is turned clockwise, as before, or the release lever is turned anticlockwise. In the latter case, a driver member 38, mounted by a bearing pin 40 on the transfer lever 34, is moved as the lever is moved by the release lever, so that its claw end 38a engages against a pin 48e on lever 48b Lever 48b thus turns to open the shutter as previously described. The shutter can be closed again by operating either lever 48b or 30, again as previously described. To make an exposure in this T-position, the shutter is opened as for interim inspection, and held open for a timed period, e.g. as determined by a watch.