Patent GB-677939-A (GB)
Title: Improvements in or relating to machines for printing and impressing text on cinematographic film
IPC: G03C11/02
Filed: 1950-05-22
Abstract: 677,939. Kinematograph films. ERTNAES, O. May 22, 1950 [July 7, 1949], No. 12802/50. Class 98 (ii). [Also in Group XVI] A machine for impressing sub-titles or like text matter on kinematograph film, of the kind in which heated text-bearing electrotypes are periodically pressed into the photographic emulsion of the film, the emulsion being preferably first softened and the film being advanced one frame at a time, includes manually controlled means for feeding the electrotypes singly into a printing position on the head of a printing press disposed below the film, mechanism for imparting vertical oscillatory movement to the printing press synchronously with the advance of the film so as to cause the electrotype in the printing position to co-operate with a pressure plate disposed above the film in order to make an impression on the film, manually operated means for adjusting the pressure exerted by the printing press against the pressure plate, and manually operated means for interrupting the impressing of the film and simultaneously bringing the electrotype feeding means into operation to replace the electrotype in the printing position with another electrotype, and for re-starting the impressing of the film when the replacement has been effected. As shown in Fig. 1, electrotypes carrying the required text matter are assembled in a magazine 1, which may be heated, and are urged towards a position from which they may be moved one by one by a sliding carriage 9 to a piston head 27 whereon an electrotype is held by a spring- loaded arm 30 against a raised portion 29. The piston head 27 includes an electric heating element 28, Fig. 2. The piston slides in a cylinder 70, and houses a spring or springs 23 bearing against the closed end 24 of the piston and against a plate 25 sliding inside the piston and retained by an apertured plate 26. When the piston moves upwards, the electrotype presses against the film 32 and a fixed plate 33. The film is advanced frame by frame by known means by a motor 57, which also drives a shaft 55 carrying an eccentric 54 which rocks a lever 43 through a link 53. The fulcrum 44 of lever 43 is adjustable by a lever 50 fast with a toothed quadrant 49, which meshes with a pinion 48 fast with an eccentric 46 operating a link 45. A lever 35 is pivoted at 42 to lever 43 and bears at one end 34 on disc 25. A lever 40 is fast with a toothed quadrant 39 meshing with a pinion 38 fast with an eccentric 37 on which the other end of lever 35 rests. Adjustment of lever 40 thus varies the pressure which the piston exerts on the film when lever 43 is rocked. The common drive for film 32 and shaft 55 ensures that the electrotype is pressed on to the film in each picture frame. To change the electrotype, lever 50 is rocked anticlockwise. This lowers pivot 44 so that the piston no longer operates, and also, through a link 66, moves a wedge 68 against a pin 69 on a toothed wheel 14. Wheel 14 is toothed, but has a cutaway portion 63a, whereby it is out of mesh with a continuously rotating pinion 64 until the action of wedge 68 on pin 69 causes the wheels to mesh. Wheel 14 is then driven one revolution until the cut-away portion is again reached, reciprocating carriage 9 by a link 11 to move a fresh electrotype into position on the piston. The electrotype previously in use is pushed out into position 18. The carriage is linked to a slide member 20 which is moved back so that the electrotype previously in position 18 may be pushed in front of it and then is pushed into a receiving magazine 21. Lever 50 is returned so that the piston begins to operate again.