Patent GB-1081733-A (GB)
Title: Photographic camera
IPC: G03B1/66
Filed: 1965-02-04
Abstract: 1,081,733. Photographic magazine cameras. AGFA A. G. Feb. 4, 1965 [Feb. 13, 1964], No. 4972/65. Heading G2A. In a photographic camera for use with two film cartridges, respectively for supplying unexposed film and for taking up exposed film, means are provided responsive to the presence in the camera of one or both cartridges, for indicating whether or not the camera is correctly loaded. In Fig. 4, one arm 23 of a pivoted lever 25 projects into a compartment 21, the arm being spring urged into contact with an edge 26a of the compartment. The other end of the lever 25 is pivotably attached to a link 29 carrying at one end a feeler 30 which projects into a compartment 22 and the other end of which link is connected with a pivoted lever 35 which carries two vanes 37, 38 and which is spring urged into contact with a stop 4. When no cartridge is in either compartment, the transparent and coloured or opaque vane 37 projects into a ray path A-B and is seen in the viewfinder ray path C-D. If one cartridge only is inserted into, say, the compartment 22, it cannot displace the feeler 30 and the vane 37 remains in the viewfinder ray path. If one cartridge only is inserted into the compartment 21, it rotates the lever 25 in the direction of arrow d and this motion is transmitted to the feeler 30 which moves in the direction of arrow e, the lever 35 being held in position by spring 39 so the vane 37 is still seen in the viewfinder. Insertion of a second cartridge, into the compartment 22, displaces the feeler back towards the position of Fig. 4, and this motion is transmitted to the lever 35 which rotates in direction c, so that the vane 37 is no longer seen in the viewfinder. If there is insufficient light for an exposure, an index marker 42 is visible. The feeler 30 may be arranged to co-operate with a control marker on the cartridge indicating the film sensitivity, so that if this sensitivity lies outside the range for which the camera can be adjusted, feeler 30 is moved either so little that the vane 37 is still visible in the ray path C-D, or so much that the vane 38 is visible therein. In another embodiment Fig. 1 (not shown), the indicating means consists of a single lever (9) each end (10), (11) of which projects into a compartment (2), (3). A pin (8) on the lever moves in a slot (7) when a cartridge is inserted, the pin co-operating with a transmission lever (16) carrying an obscuring vane (19) which is completely visible in the viewfinder when no cartridge is present, and partially visible when one cartridge is present, insertion of a second cartridge swinging the vane completely out of the ray path. In a further embodiment Fig. 5 (not shown), feelers (50), (51) project into compartments (52), (53) for cartridges (54), (55). Each feeler carries a vane (58), (63) respectively each capable of obscuring half the viewfinder ray path E-F. Insertion of a cartridge displaces the appropriate vane from the ray path. The embodiment of Fig. 6 (not shown) is for cameras having a current source (70), two electrooptical signals (73), (74), being connected thereto in parallel, the signals being visible in the viewfinder if the shutter release is actuated when one or both cartridges is absent from the camera. Each signal is connected with a contact on a feeler which is displaced by insertion of a cartridge thus breaking the circuit between the appropriate signal and the source (70). The feeler (88) associated with the signal (74) may co-operate with a control marker (93) indicating the film sensitivity so that the signal (74) is illuminated on depression of the shutter release if the sensitivity of the inserted film lies outside the range for which the exposure mechanism of the camera can be adjusted. A simpler electrical indicating system is used in the embodiment of Fig. 7 (not shown), two feelers (100), (101) again being provided, but this time they are connected in series with one optical signal (112) which signal is only seen on depression of the shutter release when both cartridges are present in the camera. As before, the sliding contact feeler (101) may be arranged to co-operate with a control marker (120) indicating the film sensitivity. In a further embodiment Fig. 8 (not shown) employing the indicating system already available in the camera two feelers (135), (145) are provided, the feeler (135) forming a switch which is closed on insertion of a cartridge, which switch is in series with a photo-electric cell (140) and a galvanometer (143) in the metering circuit (152). The feeler (145) is arranged to short circuit the galvanometer (143) when there is no cartridge present in the compartment (132), or when a control marker (150) indicates that the film sensitivity is outside the range for which the camera can be adjusted, so that the galvanometer needle; which is visible to the user, remains in an extreme position. In another embodiment Fig. 9 (not shown), the exposure metering system comprises a moving coil galvanometer (160) provided with a needle (161) the position of which is sensed by a movable jaw (164), which jaw is connected with a setting member (169) for shutter speed and/or diaphragm aperture and also with a lever (178) which bears markers (180), (181) one of which is always present in a ray path G-H to indicate whether or not it is possible to make an exposure. When none or only one cartridge is present, the arm (183a) of a blocking lever (183) is positioned to prevent movement of the jaw (164) when a trip rod (170) is depressed. Insertion of both or the other cartridge rotates both or one feeler (199), (200) and this movement is transmitted to slide (186) which moves in a direction opposite to arrow h and rotates the lever (183) to allow movement of the jaw (164). The jaw (164) is locked if film of the wrong sensitivity is inserted. In the embodiment of Fig. 10 (not shown), absence of one or both cartridges causes a slide (211) to block a honeycomb lens (214) and prevent light therefrom from reaching a light-sensitive element (210) connected with a galvanometer (217). The slide is arranged to obscure the lens (214) if the film sensitivity of the inserted film is outside the range for which the camera can be adjusted. In a further embodiment Fig. 12 (not shown), absence of one or both cartridges locks the film transport mechanism, as does insertion of a cartridge containing film of sensitivity outside the camera range.