Patent GB-422815-A (GB)
Title: Improved method and device for mechanically recording oscillations particularly sound oscillations
IPC: G11B11/00
Filed: 1934-01-08
Abstract: 422,815. Recording sound and the like. NAAMLOOZE VENNOOTSCHAP PHILIPS' GLOEILAMPENFABRIEKEN, Emmasingel, Eindhoven, Holland. Jan. 8, 1934, No. 680. Convention date, Jan. 9, 1933. [Class 40 (ii)] A method of mechanically recording sound or like vibrations on a carrier, preferably a film, in such a manner that the record can be reproduced by optical means, consists in using a carrier having formed thereon prior to or during recording a groove or protuberance extending in the direction of recording, which groove &c. is deformed due to flexure of the carrier, during the recording operation, by the recording device or additional means, so as to produce a track having width variations the shape of which is influenced by this deformation. Figs. 1, 2 and 8 show a machine for carrying out the invention, in which is used a film 1 having a transparent base of material such as celluloid, which may have an opaque outer layer of graphite, paint, or the like, and an intermediate soft layer, e.g. of gelatine. When the opaque layer is omitted, during the recording or subsequently the carrier is suitably treated to distinguish the sound track in transparency from its surroundings. The film passes under a recording chisel 5 which has connected to it by means of arms 6, a roller 7, the chisel and the roller bearing on the film over a groove 4 formed therein. The groove may be made by a pair of rollers 11 as they pull the film from a drum 10, from which it is fed past the recordng member 5 to a take-up drum 23. Guide rollers 19, 20, which are profiled in accordance with the shape of the grooved film, are arranged as shown, and the film is flattened after recording, by rollers 21. Instead of the rollers 11, a die may be used to groove the film ; or the groove can be cut out by a chisel or milling cutter. The recording member with the attached roller 7 are mounted on an adjustable arm 16, the means for vibrating the recorder not being shown. The groove 4 is such that as the straight-edged recording chisel vibrates, the roller 7 tends to flatten the film at each downward movement of the tool, so that the width variation of the track produced by the tool, as shown in Fig. 5, is influenced by the deformations due to flexure of the film. The chisel in its various positions cuts into the film material to a substantially constant depth. The film may be severed along the central line V-V, and each half used for reproduction. Instead of securing the roller 7 to the recording member, it may be separately vibrated, e.g. by means of an electromagnet, in accordance with the oscillations to be recorded. In a further modification, Fig. 6, the chisel 9 engages a deformable protuberance formed on the film. Another alternative consists in vibrating the support over which the film moves, whilst the recording tool is stationary. The Specification as open to inspection under Sect. 91 shows in Fig. 10 (Cancelled) a device for recording on a transparent carrier, comprising a cutting or pressing tool 26 which supplies dyestuff to the track as it is formed. This subject-matter does not appear in the Specification as accepted.