Patent GB-1018497-A (GB)
Title: Electrical operating assembly for a photographic camera
IPC: G03B17/42
Filed: 1962-09-11
Abstract: 1,018,497. Photographic cameras. AGFA A.G. Sept. 11, 1962 [Sept. 16,1961], No. 34741/62. Heading G2A. A self-contained electrical assembly for attachment to or incorporation in a photographic camera includes an impulse operable release means for effecting electrical actuation of the shutter release of the camera, an electric motor for coupling to the camera film advance drive mechanism and a changeover switch for coupling alternatively the release means or the motor to a power source, all arranged so that, from an idle position in which the release means is connected to the power source but the circuit is broken, on externally making the current to provide an electrical impulse, the camera shutter release is actuated and the changeover switch is thrown to cut out the release means and to complete the motor circuit, means being provided operable by the motor to throw the switch again at the completion of the desired motor running period. As shown, the impulse operable release means is an electromagnet 2 connected to one side of a battery 3 in parallel with the motor 1 which drives the film advance mechanism. The opposite side of the battery is connected through the pole 5 of a changeover switch to either the opposite side of the motor or to a terminal 9 which through an externally completable circuit makes connection through contact 8 to the electromagnet. This external circuit may be completed by a switch operated by a passing vehicle or a timed programme of events or by photo-cell pulses. Such circuit closure energizes the electromagnet 2 which rotates lever 13 clockwise and causes lever 15 to turn anticlockwise on its pivot 15d, so depressing the camera release 10, and also via lug 13c engaging a lug 16a rotates lever 16 clockwise about its shaft 18. This causes a lug 16b to move clear of and allow anticlockwise movement of lever 17 fixed on shaft 30 which carries a cam surface 32 for engagement by a lever 36 pivoted at 37. When the energizing closure across terminals 8, 9 ceases, levers 13, 15, 16 return to the rest position, while lever 17 rotates further anticlockwise until arrested by the lug 16c to bring lug 20a on a rotatable segment 20 into the path of a pin 26a on gear 26 of the film advancing train and operates the pole of the changeover switch to energize the motor 1 which drives the film advancing mechanism cam 28a which may operate a rapid film advance lever, and sets the shutter unless this is of the everset type. As pin 26a moves away from lug 38b, lever 38 latches lever 36 to hold the motor circuit closed. When pin 26a meets lug 20a and drives the segment 20 anticlockwise, shaft 30 is driven clockwise to return the lever 17 to the position shown past the resiliently yielding lug 16b, and when the gear 26 has made one revolution its pin 26a engages lug 38b to free the lever 36 from its latch so that this causes pole 6 to move away from contact 7, breaking the motor circuit, and to move on to contact 6 ready for the next exposure. In modifications, reduction gearing may be provided between the sleeve 21 and spindle 27 to provide several motor shaft revolutions per film advance, lever 13 and electromagnet armature 12 may be connected rigidly or by a spring, the cam 32 could be formed on the lever 36 and the camera release may be also manually operable. To avoid battery discharge when at the end of the film a complete frame advance cannot be made the arrangement of Specification 926,258 is provided to break the motor circuit start to the electromagnet 2.