GB399043A - Improvements in and relating to the recording and reproduction of sound - Google Patents

Abstract

399,043. Sound recording or reproducing apparatus. I. G. FARBENINDUSTRIE AKT. - GES., Frankfort on- Main, Germany. Dec. 2, 1932, No. 34166. Convention date, Dec. 2,1931. [Class 40 (ii).] Comprises means for recording a helical sound-record upon an endless record band or for reproducing from such a record, wherein the speed of the relative transverse movement between the recording or reproducing device and the band can be adjusted to suit the length of the band. The invention is shown in Fig. 1 as applied to mechanical recording or reproducing apparatus. A motor 3 drives, through a gear box 4 and shaft 5, a friction wheel 6 which serves to rotate a disc 7. Rotation of the disc 7 is transmitted through a worm 12 to a disc 13 on which is mounted frictionally a crank disc 14 connected by a crank 15 with a recording or reproducing device 10, so that the device 10 is moved across the width of the record band 2 as the latter travels in the direction of its length. The speed of movement of the device 10 is adjusted to suit the length of the record band by means of a pointer 9 movable over a dial 11 to adjust the friction roller 6 in position along a radius of the disc 7. A stop 15a, in the path of the crank pin on the disc 14, prevents further travel of the device 10 at the end of its transverse movement. In the modification shown by Fig. 2 the recording or reproducing device 1 is kept stationary while the record band 2 is moved transversely as well as longitudinally. For this purpose the record band support 16 is fixed to a slide 17 which carries a roller 19 bearing against one of a number of cams 20. The gradients of the cams are varied to suit different lengths of record band and the cam shaft can be displaced to bring either of the cams into contact with the roller 19. The invention may be applied to optical sound-recording or reproducing apparatus.