| 摘要 |
A compact fluorescent tube comprises at least one U-shaped main tube part (11) and a base (12). Each main part has two straight tubular legs (14) of circular cross-section and a connecting tube (15) of rectangular cross-section. The connecting tube is joined to the cylindrical peripheral surface of respective tubular legs at regions adjacent the ends of the legs. The end surfaces (16) and one side (17) of the connecting tube form together a coherent flat end surface (18) on the U-shaped main part of the tube. A suitable method for manufacturing such a compact fluorescent tube comprises heating and bending straight glass tubes into U-shaped main tube parts, and blow moulding to form the connecting tube between the legs. Bending is effected around a first mould part which exhibits a channel-shaped abutment surface or accommodating the glass tube. A second, complementary mould part is provided for shaping the outer peripheral surface of the glass tube. The mould parts are caused to move relative to one another, such that the molten glass in the U-bend can collect in a dish-shaped part located in the second mould part. Finally, gas under pressure is introduced into the glass tube, so as to press the tube against the mould walls, such that the main tube parts are given their final shape. |
