Improvements in and relating to apparatus for coating hollow glassware

摘要

657,871. Vapour burners; electric lamp bulbs. BRITISH THOMSON-HOUSTON CO., Ltd. March 21, 1949, No. 7636. Convention date, March 27, 1948. [Classes 39(ii) and 75(i)] Apparatus for providing the inner surface of an electric lamp bulb or other hollow glassware with a light-diffusing coating by the deposition of particles of a fume produced within the hollow body, as described in Specification 653,323, comprises a burner with a hollow stem portion 28, Fig. 3, containing a combustible liquid, e.g. ethyl silicate, and surmounted by a removable cap 23 provided with a closed upper end and peripheral apertures 27, these apertures being adjacent to a hollow head 26 formed by flanging the upper end of the stem 28 and a surrounding tube 35 which provides an annular passage for a gas, e.g. oxygen, which escapes laterally through holes 25 in the head 26. The flame resulting from the combustion of the ethyl silicate is discharged between the cap 23 and head-flange 24, and the fume is drawn into the contiguous radial stream of oxygen issuing from the holes 25. As shown, the cap 23 has a stem 27a provided with three relatively large apertures 27 which are staggered with respect to three groups of openings 25 in the adjacent head 26. In a modification, Fig. 4 (not shown), the groups of openings through which the oxygen passes are associated with an annular deflecting ring provided with an oblique upper edge. In applying the coating of the fume the burner is located within the lamp bulb or other body which is mounted on a holder arranged to rotate at constant speed and also to have a cam-controlled vertical movement. Ethyl silicate is fed to the hollow stem of the burner from a gravity bottle connected to it by a flexible tube. The Specification as open to inspection under Sect. 91 comprises also a burner adapted to project the fume upwardly and outwardly from an annular space 49, Fig. 6, (Cancelled), formed by a frusto-conical cup 57 within a well 62 in a head 46 provided with a tubular stem 54 through which ethyl silicate is fed. The vaporized liquid enters the space 49 through lateral apertures 48. Oxygen is fed between tube 54 and a surrounding tube 55 and after passing through longitudinal grooves 56 into a space between the head 46 and an outer shell 50, has a swirl imparted to it by a helical ridge or partition 53 between the members 46 and 50. This subject-matter does not appear in the Specification as accepted.