Patent GB-287981-A (GB)
Title: Electric flashlight photographic camera
IPC: G03B17/53
Filed: 1927-07-23
Abstract: 287,981. Murray, W. July 23, 1927. Cameras, reflex; cameras combined with flash-lights and like apparatus; shutters with sliding plates. - A camera, for use by day or by night, comprises a single control member which can be selectively operated to allow of focusing the camera through the opened shutter while focusing lights illuminate the object to be photographed, to take the photograph by the light of a magnesium flash cartridge, and to allow the film to be wound back on a removable spool after the photograph has been taken. The camera, Fig. 1, comprises a casing 1, one end of which is closed by a box 2 slidable relatively to the casing 1 on a box-frame 3 extending into the casing 1, a rack on the box 3 meshing with a pinion 8 on a box 4 and a sprocket 11 on the pinion shaft being chain-driven from a sprocket 13 on a spindle 14, engagable with the operating knob 15. The film is stretched between a removable spool 18 and a spool 17. Pivoted baffles 23, 24 are linked to the ends of a lever 25 pivoted on a stud 26 which also carries a lever 27 linked to a crank-pin 29 on a disc 30 on the spindle 14. The disc 30 has ratchet teeth and is prevented from backward movement by a pawl 30a. A hinged door 31, with collapsable side wings 31a, is attached to a lever 32 linked to the lever 27. The top face of the box 4 consists of frosted glass 4<a> and the upper face of the baffle 23 is silvered to form a reflector. On rotating the disc 30, the lever 25 is swung to bring the baffles 23, 24 together to shield the film from light through the open shutter. A flexible member 24<c> on the baffle 24 is adapted to ensure a light-proof joint between the baffles. The rotation of the disc 30 also raises the door 31 to the position shown in Fig. 3, so that the operator looking into the camera through the door 31 sees the image, reflected by the baffle 23, on the frosted glass 4<a>. The shutter is actuated from a vertical bar 35. Fig. 2, sliding on guides and having at its upper end an extension 37 slotted to engage a pin on the lever 32 so that the extension 37 may move longitudinally with the box 2 without moving the lever 32, but so that the opening or closing of the door 31 causes the rod 35 to fall or rise. The shutter comprises a spring-controlled sliding plate 39 normally closed. Bell-crank levers 44, 45 are adapted to open the shutter at predetermined times, a stop 46 on the downward movement of the rod 35 engaging one arm of the lever 44 to abut the other arm against a spring stop 44<a> to open the shutter. On further movement, the lever 44 passes the stop 44<a> and the shutter closes. On the upward movement of the rod 35, the lever 45 is similarly actuated by a stop 50 to open and close the shutter. In the downward movement of the rod 35, a contact 48 thereon bridges fixed electric contacts 49<a>, 49<b> to complete the circuit through a 30-volt battery carried in the box 3 and light up focusing bulbs 42 which are provided with reflectors 43. The bulbs are wired in series. In the upward movement of the rod 35, the contact 48 bridges contacts 49<b>, 49<c> to complete a battery circuit to ignite a magnesium cartridge. Modified shutter opening mechanism for quicker opening is shown in Fig. 10 and comprises a bell-crank lever fitting in a slot 39a in the shutter, the free end of the lever being actuated by the stops on the rod 35. Shutter-opening mechanism as shown in Fig. 11 may also be used, pivoted ievers 62, 63 being actuated for part of the movement in either direction by projections 64 on the rod 35, and for the rest of the movement by a spring 65. The lever 62 strikes a shutter frame 66 to open or close the shutter. At the front of the camera an annular plate 51 is mounted in circular guides 52, and is divided into sections each comprising grooved guides 53, Fig. 5, and bow-string electric contacts 54, the contacts of the lowermost section bearing on fixed contacts 55 in the battery circuit. In each section is placed a magnesium cartridge, Fig. 8, a flange 56<a> of the cartridge fitting the guide 53, and the contacts 56<c> extending through the flange. A fuse wire 56<d> joins the contacts 56<c> together. When the cartridge is in position, the contacts 56<c>, 54 meet so that on completion of the circuit through the contact 48, the wire 56<d> of the lowermost cartridge ignites the magnesium powder in a cardboard container 56b to produce a flash. Teeth 51<a> on the back of the plate 51 are adapted to be engaged by a projection on the rod 35 to rotate the plate 51 to feed a new cartridge into position. A pawl 51b prevents backward rotation of the plate 51. Fig. 4 shows the means of operation of the camera from the knob 15. The sprocket and the disc 30 are respectively secured to bushes 14<a> 14<b> in the film spool 17 and have dogs or clutch teeth on their inner ends to engage with similar members on a clutch 14<c> fitted at the inner end of the spindle 14, the clutch 14<c> being engageable with the bushes 14<a>, 14<b> at will, and being free from the spool 17 when engaged with either bush 14a, 14b. In operation, the knob 15 is pushed inwards and turned so that the clutch 14<c> engages the bush 14b, further turning of the knob 15 raising the baffles 23, 24 to shield the film, opening the door 31 and the shutter 39, lighting the lights 42 and advancing the plate 51 one section. To adjust the lens focus, the hnob 15 is then pulled outwards until the clutch 14<c> engages the bush 14a so that rotation of the knob movies the parts 1, 2 with respect to each other. The knob is then pushed in to rotate the bush 14b to close the shutter, return the baffles 23, 24 to the horizontal position, close the door 31 and extinguish the lights 42, again open the shutter and ignite the cartridge. To readjust the relation of the parts 1, 2, the knob 15 is brought to central neutral position. The film may then be rewound on the spool 18. A partition 58 is provided in the box 3 to localize the light through the door 31. A spring 61 presses the battery against the terminals 59, 60.