DISCHARGE LAMP COMPRISING ELECTRODES HAVING A CONICAL SLIP PART

摘要

A lamp vessel (3) of a discharge lamp comprises two electrodes (40), wherein a part of each electrode (40) extends in a plug (23) arranged at an end of the lamp vessel (3). The electrode (40) comprises a base part (41), through means of which the electrode (40) is fixed to the seal (23). Furthermore, the electrode (40) comprises an intermediate part (43) having a conical outer surface (44). An inner surface (51) of the plug (23) fits closely on the outer surface (44) of the intermediate part (43) of the electrode (40). In case the electrode (40) expands as a result of an increase of the temperature, the conical outer surface (44) of the electrode (40) slips with respect to the inner surface (51) of the plug (23), wherein stress build-up is avoided. In this way, breaking of the plug (23) is avoided.