Method of and apparatus for forming discharge tubes of low-pressure discharge lamps

Abstract

There is disclosed a method for forming a discharge tube for a low-pressure discharge lamp. In the method, an end of a section of the discharge tube is fastened with first clamping means, and a second end of the section in held in an oriented position. The section is heated to a softening temperature, and a bending moment is exerted on the section between the first end and the second end for achieving the desired radius or direction of curvature of the section. The holding of the second end of the section and the exertion of the bending moment on the section are effected at least partly with another re-solidified section of the discharge tube which is adjacent to the softened first section. An apparatus for performing the method is also disclosed. The apparatus comprises first and second clamping means for positioning the ends of a bending section of the discharge tube in an oriented position relative to each other, and for exerting a bending moment on the ends. The second clamping means is also used for positioning the ends of a starting bending section relative to each other. Heating means are provided for heating the bending section to a softening temperature, and controllable support means for positioning the first and second clamping means. Control means are used for synchronizing the operation of the controllable support means. The first and second clamping means and the heating means are suitable for achieving a desired radius or direction of curvature of the bending sections heated to the softening temperature.

Dependencies are inferred from the claim text.