GB624874A - Improvements in sound recording and reproducing machines - Google Patents

Abstract

624,874. Sound on film. KUHLICK, J. M. Sept. 11, 1946, No. 27267. [Class 40 (ii)] In an apparatus for recording and reproducing sound on film by means of a stylus, means are provided for fixing and adjusting the film support 12 relatively to a rigidly fixed transducer U. The support 12 consists of two a lower part 25 mounted on a shaft 26, and parts, an upper part 38 suspended about an axis 45 on the lower part 25. The lower part 25 is maintained in a fixed position against the tension of a spring 29, by means of a spring-loaded plunger 32 which locates itself in a recess 32<SP>11</SP> in a mounting plate 3 after the support 12 has been lowered and lifted when removing and replacing the film. The upper part 38 is adjustable relative to the lower part 25 and the transducer U by means of a knurled-headed screw 51, a leaf-spring 50 on the lower part 25 pressing on a pin 49 on the upper part 38 to hold the latter against the end of the said screw 51. The upper part 38 also has a spring- loaded flange 40 in order to provide for variations in the width of the film. The film is drawn over the upper part 38 of the support 12 from spool 5 to the spool 4, by means of a motor M and a worm and wheel gearing to a shaft 10 carrying a film feed wheel 11, against which the film is pressed by a roller 13 on a spring-loaded arm 14. The shaft 10 is coupled by a slipping belt 6<SP>1</SP> to the take-up spool shaft 6, while a similar belt 22<SP>1</SP> coupled to the shaft 7 engages a fixed pulley 22<SP>11</SP> so that the spool 5 is held back under suitable tension to prevent unrolling. The transducer U is adjustable laterally with regard to the film in order that the stylus may trace a path offset from the centre line of the film and a second track traced after the positions of the spools 4, 5 have been interchanged on the screwed shafts 6, 7.