GAS PRODUCING APPARATUS AND METHOD AND APPARATUS FOR MANUFACTURING OPTICAL WAVEGUIDE AND OPTICAL FIBER PREFORM

摘要

There disclosed a gas producing apparatus for producing a glass formation gas required in an FHD method, a VAD method or an OVD method. A glass formation material is supplied intact in the form of a liquid to a vaporizer, and the supply quantity of this liquid material is controlled directly by a liquid flow rate control means while the material is kept in the form of a liquid. In addition, at the same time the liquid material is vaporized by the vaporizer, a fixed amount supply means supplies an inert gas or a combustion gas at a fixed flow rate to the vaporizer. Since this prevents a pressure rise in the vaporizer, the liquid material is stably supplied to the vaporizer. Therefore, a fixed amount of vaporization of the liquid material is constantly performed in the vaporizer without being influenced by variations in the atmospheric pressure. Furthermore, since the vaporized material is supplied to a burner together with the inert gas or the combustion gas supplied at a fixed flow rate from the fixed amount supply means, the burner injects a fixed amount of the material gas at any instant.