Method for marking quartz glass lamps and quartz glass lamps produced using this method

#The invention relates to a method for marking quartz glass lamps having at least one fusible metal foil which is surrounded by quartz glass, for supplying electric voltage to luminous means arranged in the interior chamber of a lamp vessel. The luminous means is either an incandescent filament of an incandescent lamp or an electrode for producing a discharge arc in a discharge lamp. In particular, it relates to a method for marking halogen lamps, i.e. either incandescent halogen lamps or discharge lamps with a halogen fill. Furthermore, the invention relates to a quartz glass lamp produced using the method.

#Various types of methods are known for marking quartz glass lamps, in particular halogen lamps. In particular, lamps of this type are marked or stamped using what is known as the “pad printing” method.

#However, this method leads to a number of technical problems. For example, the stamping using the “pad printing” method is a method which involves contact with the lamp, which may cause damage to the lamp. Furthermore, a dedicated stamping block has to be produced for each lamp identifier, leading to high costs. Therefore, date stamping of the quartz glass lamps which are to be marked is scarcely possible. In addition, changing the block involves standstill times. A further drawback is that the stamping blocks become worn, thus considerably increasing the risk of stamping errors. Furthermore, the known method has the drawback that the stamping ink has to be fired in using separate heating torches. Another drawback is that the stamp may become scratched over the course of time. Finally, a further drawback results from the fact that the pad printing stamp cannot be checked by means of an automated image-processing system, since the fusible metal foil arranged in the background of the marking causes contrast problems.

#The invention is to be explained in more detail below with reference to an exemplary embodiment.

#The FIGURE diagrammatically depicts two fusible metal foils 10, 12, in particular two molybdenum foils, which on one side are conductively connected to the ends 14 of the luminous incandescent filament 15, which is arranged inside a lamp vessel (not shown), of an incandescent halogen lamp and on the other side are conductively connected to in each case one contact pin 18, 20, in order to ensure the supply of electric voltage to the incandescent filament 15. Furthermore, it can be seen that the fusible metal foils 10, 12 each have a marking area 16. The marking of the marking areas 16 takes place through the quartz glass (not shown) which surrounds the fusible metal foils 10, 12, by means of a laser (not shown). The thickness of the fusible molybdenum foils is usually approximately 10 μm to 100 μm. The width and length of these molybdenum foils usually measure from a few millimeters to a few centimeters.