GB1468338A - Cine-film cameras - Google Patents

Abstract

1468338 Cine cameras K VOCKENHUBER and R HAUSER 11 April 1974 [16 April 1973] 52564/75 Divided out of 1467342 Heading G2E A cine-film camera selectively capable of exposing a silent film contained in a cartridge of a first type and a sound film contained in a cartridge of a second type, comprises a cartridge compartment, a sensing device extending into the compartment for determining the type of cartridge inserted, first and second drive means for the film, a motor for providing at least the first drive means, first control means for maintaining the motor speed constant and second control means for maintaining a constant length of film between the first and second drive means, the sensing device being arranged to render one or other of the two control means inoperative in dependence upon the type of cartridge inserted. Fig. 3 shows one form of the sensing device, consisting of two spring- loaded levers 31, 42, in the position occupied when a silent film cartridge (1), Fig. 1A (not shown) is inserted into the cartridge space 4. The bottom wall 25 of this space is urged upwards by springs 28 as far as it will go when the cartridge is in position. A slide 32 covers an aperture 36 in the camera wall, so that a microphone plug cannot be inserted into the socket 35. When a sound cartridge (2), Fig. 1B (not shown) is inserted into space 4, the extra length of the cartridge pushes bottom wall 25 further down from the Fig. 3 position, so that levers 31 and 42 are pivoted respectively clockwise and anti-clockwise. Thus slide 32 is pushed upwards until an aperture 41 therein coincides with aperture 36, thus making socket 35 accessible. At the same time a switch 43 in the sound recording circuit is closed. Fig 5 shows a conventional fly-wheel-carrying sound-spindle 55 which co-operates with a pinch roller 56, under the action of a spring 59. When a silent cartridge is in position, the parts shown in Fig. 5 are drawn to the position shown by a spring (50), Fig. 6 (not shown) which is more powerful than spring 59. Thus lever 57 carrying roller 56 is pivoted against spring 59 to bring roller 56 out of contact with spindle 55. When a sound cartridge is introduced, this thrusts against the stronger spring (50), so that lever 57 pivots to bring roller 56 against spindle 55. The film can be driven by two motors, motor 62 and another motor (20), Fig. 2 (not shown), the latter not being engaged with the film when a silent cartridge is in position. In this case the film is driven by a claw feed associated with motor 62, the indexing frequency of the claw being controlled by a centrifugal governor 63. In sound film operation the film is additionally driven by the second motor (20) which is a speed-stabilized motor, so that any additional speed regulation would be detrimental to the running of the film. The governor 63 in this case is therefore arranged to be switched off by the sensing device, which also connects a further regulating device 68 into the circuit. This senses the size of the film loop formed between the claw feed and the sound spindle 55, and maintains it constant by briefly switching off the motor 62.