Patent GB-103407-A (GB)
Title: The Synchronisation of Machines for Recording and Reproducing Sounds & Movements.
Inventor: VERITY CLAUDE HAMILTON
IPC: G03B31/00
Filed: 1916-05-11
Abstract: 103,407. Verity, C. H. May 11, 1916. Differential speed indicators.-The speed of a phonograph is adjusted into synchronism with a corresponding kinematograph film by the operator watching a tape which bears a series of marks corresponding to marks on the picture film. The camera, Fig. 5, has two geared shafts D<1>, G<1>, one of which carries a sprocket E<1> driving the film A<1>, the other carrying a drum M<1> with a metal segment. intermittently connecting the brushes O<1>. A counter T' is also operated from the drum shaft G<1>. Whilst the pictures are being taken, the phonograph motor G, Fig. 1, running at normal speed, moves a tape T under a marking- roller or perforator O, which is brought down into contact with the tape upon the energization of a magnet N in circuit with the brushes O<1>, Fig. 5. At this time, no sounds are being recorded, but the tape T is given a series of marks, which are afterwards numbered or lettered consecutively, and these marks correspond to similar marks on the film A<1>, either made automatically during exposure, or by hand after development. As the pictures are being taken, a shorthand writer watches the counter T<1> and makes notes on correspondingly numbered sheets of the words uttered. In order to record the sounds, the pictures are projected on a screen, and the phonograph is set up in such a position that the operator can see the consecutive numbers projected on the screen through the film. The actors speak into the phonograph horn and time their utterances by watching the pictures, the shorthand writer watching a counter on the kinematograph projector, similar to T', and prompting the actors through a telephone. The phonograph operator, by a handle X, so adjusts the speed of the phonograph motor G that the numbers on the tape T agree with those projected on the screen. Duplicates of the film A<1>, tape T, and phonograph record are then made and circulated, and in reproducing the combined film and phonograph record in a picture theatre, the film is used in an ordinary projector, and the phonograph operator controls the speed of the phonograph with the aid of the tape T, as in the sound-recording operation. As shown in Figs. 1 and 4, two phonographs are used driven by separate motors G, either of which may be started by moving a switch Y, which also connects up the corresponding magnet N to the brushes 0', Fig. 5. The turntables C are driven through belts H, worm shafts E, and spindles D, and the worm shafts E carry sprockets F for driving the tapes T. The tapes T are uncoiled from spools L on to spools U mounted by spring clips on their shafts, one pair of shafts J being driven by belts V. The marking-rollers O are arranged between the tapes T and inking-pads P<2>, and are carried on spring- controlled pivoted arms Q, to which are attached armatures P for the magnets N. The records have eccentric, as well as central, holes to determine their position on the turntables, which have corresponding pins. When an opera is being recorded, the record of the orchestral music is taken during the acting of the opera, and the vocal music is subsequently recorded, the turntables being positively geared to prevent variation of speeds during reproduction.