Patent GB-191020016-A (GB)
Title: An Improved Reflex Photographic Camera.
IPC: G03B19/12
Filed: 1910-08-27
Granted: 1911-05-18
Abstract: 20,016. Newman, A. S., and Newman & Sinclair. Aug. 27. Cameras, reflex; shutters with rotating blades or disks.-In a reflex camera with a blade-anddisk shutter, an auxiliary protecting-screen b, Figs. 8, 9, 10, and 11, is hinged below the mirror a. The shutter, mirror, and screen are connected to work as follows. After an exposure, the mirror and screen are horizontal, Fig. 8, and the shutter is looked. When the mirror and screen have been set for focusing, the shutter can be set, and the lens is exposed, Fig. 9. On releasing the mirror a, the blade c' of the shutter is released and swings up to close the lens, Fig. 10, being connected to the blade c by a spring p<3>, Fig. 7, and normally held by stops c<5>, c<6> at an angle of 120 degrees. The screen b is then raised, and the shutter released to make the exposure, Fig. 11. The mirror a, Fig. 1, and screen b are pivoted on the same shaft a<1>. The mirror a is connected by a link a<2>, Fig. 1, to the setting-arm e. The screen b has a spring tending to lower it, and is connected to move with the mirror by the links b<1>, b2. To set the mirror, the shaft e<1> is rotated, drawing down the mirror and the screen b with it, and the mirror is held by a pin e<3> engaging behind the lever f. The shaft e<1> has a spring stronger than the spring acting directly on the screen b, and when the release lever f<3> is operated, the arm e raises first the mirror, and, when the pin a<4> engages the closed end of the slot b<3>, the further motion raises the screen also. The shutter is operated in conjunction with the mirror and screen mechanism through a flexible and extensible shafting comprising bevel-gearing operated from the shaft e<1>, a short shaft g<1>, a universal joint g<3>, extending shafting h, i, and a universal joint j<2>, and a short shaft with an arm j<3> actuating the shutter. The shutter blade c', Fig. 7, is fixed to a plate c<3>, which rotates freely on the sleeve of the plate c<2> carrying the blade c, and the blades are normally kept separated at an angle of 120 degrees by the coiled spring p<3> and stops c<5>, c<6>. The blades rotate on a spindle p<2> between the lens carrier o and the rear plate p. The plate c<2> is connected to the disk n by a pin c<8>, and the plate n is mounted on the spring shaft n<2> of the shutter. On setting the mirror, a pin j<4>, Fig. 4, on the arm j<3> releases an arm k of a lever k, k<1>, and allows the other arm k<1> to be moved by its spring into the path of a pin n<3> on the plate n of the shutter. The pin j<4> next releases the arm l and allows an arm l<1> to be moved by its spring into the path of the pin c<6>. Finally, the pin j<4> engages an arm m and disengages the arm m<1>, thus unlocking the shutter. As the shutter head n<4> is wound, the pin c<6> on the shutter blade c<1> is stopped by the arm l<1> in the position shown in Fig. 9, and on further winding, the pin n<3> on the plate n engages behind the arm k<1> and retains the shutter in the set position, Fig. 9. On operating the release f<3>, the mirror is raised and the pin j<4> releases the arm m, which allows the arm m<1> to move against the periphery of the notched disk n to lock the shutter at the end of the exposure. The pin j<4> then engages the arm l, thereby disengaging the pin c<6> from the arm l<1>, whereupon the blade c<1> is drawn by the coiled spring p<3> to the position shown in Fig. 10. In this position, the lens is covered and the auxiliary screen is then raised, and at the end of the motion, the pin j' engages the arm k and releases the pin n<3>, and the exposure takes place under the influence of the shutter spring n<7>. The shutter is also locked by the arm m<1> engaging the disk n, Fig. 4. A dash-pot q may be adapted to control the exposure. A lever r is used for time exposures. When the mirror and screen are released, the blade c<1> closes the lens as usual. A slight pressure on the lever r<1> releases the arm r from one notch in the plate n, and the shutter exposes the plate, and is let go immediately to engage the second notch corresponding to the open position of the shutter. The lever is again released to complete the exposure.