Patent GB-805933-A (GB)
Title: Improvements in or relating to photographic shutters
IPC: G03B9/22
Filed: 1955-03-30
Abstract: 805,933. Photographic shutters. GAUTHIER G.m.b.H., A. March 30, 1955 [May 3, 1954, No. 9301/55. Class 98(1) In a photographic camera shutter which includes electrical contacts for making flash exposures, a self-timer escapement mechanism with a disengageable part for making delayed exposures, a flash-contact escapement forming part of the self-timer escapement without the said disengageable part, means for setting the contact escapement simultaneously with the setting of the shutter, and a control member which is adjustable, both when the shutter is set and when it is unset, between a "V" position in which the exposure is made after a delay produced by the self-timer escapement, an "M" position in which the flash contacts are closed before the complete opening of the shutter to allow for a flash delay, and an "X" position in which the flash contacts are closed substantially simultaneously with the complete opening of the shutter, an interlocking mechanism is provided within the shutter casing which automatically returns the control member to the "X" position, after an exposure has been made with it in the "V" position, at the latest when the shutter is set for the next exposure. As shown in Fig. 1, the flash contacts comprise a central pin 11 which may be contacted by a spring 12 or lever 13. The spring 12 is pressed into contact with the pin 11 by an arm 14 actuated by a pin 7 on the blade ring and contact is made when the blades are fully open. Lever 13 may pivot to contact pin 11 as soon as the blade ring begins to move since it removes pin 15 from the path of lever 13. Lever 13 is prevented from moving however when the control ring 16 is set with its pointer 16<SP>11</SP> to the "X" or "V" settings since the projection 16<SP>1</SP> blocks its movement. Thus only in the "M" position are the flash contacts closed before the shutter blades are fully open. The control ring 16 may be provided with an arm 16<SP>1v</SP>, ,Fig. 3, which tensions the spring 103 when the ring 16 is set to the "V" position where it is held by the leaf spring 101. The escapement is constructed as in Specification 770,041 and is wound with the shutter setting lever 6 by arms 42, 39. When it is almost run down and the shutter blades have closed, arm 42 comes into the position shown in dotted lines in Fig. 3 and depresses the spring 101, thus releasing arm 16<SP>1v</SP>, and then spring 103 returns the ring 16 to the "X" position. Alternatively the arm 16 may be held by a leaf spring 105, Fig. 4, and released therefrom by an arm 6<SP>1</SP> on the setting lever 6 just before the lever comes to rest after the shutter blades have closed. In either case the ring 16 is prevented from moving past the "X" position into the "M" position by a spring 102, shown in Fig. 3. In further embodiments, adjustment of the control ring 16 from "X" to "V" positions is prevented in the unset position of the shutter. Thus a latch 106, Fig. 6, may be provided on arm 42 which is turned in a clockwise direction against a stop 108 by a spring 107. An arm 16<SP>y</SP> on ring 16 is in the position shown in full lines in Fig. 6 when the ring is in the "X" position, and bears against latch 106 when the shutter is unset, as shown, and the ring cannot be moved to the "V" position until the shutter is set. In Fig. 7, a plate 110 is pivoted by a slot and pin to the fixed plate 37 and linked to the delay escapement setting lever 39 at 109 so that it rotates in an anti-clockwise direction as the shutter is set (full lines show unset position in Fig. 7). When the ring 16 is in "V" position, an arm 113 thereon is engaged by the projection 110<SP>1</SP> on plate 110 and moved to "X" position when the shutter is set. When unset and in the "X" position, a further projection 110<SP>11</SP> prevents arm 113 being moved back to "V" position.