Ceramic discharge vessel for a high-pressure discharge lamp, having a filling bore sealed with a plug, and method of its manufacture

摘要

PCT No. PCT/EP94/00324 Sec. 371 Date Jul. 11, 1995 Sec. 102(e) Date Jul. 11, 1995 PCT Filed Feb. 4, 1994 PCT Pub. No. WO94/18693 PCT Pub. Date Aug. 18, 1994To provide a tight seal for a fill bore in the wall or an end plug of a discharge vessel for high-pressure discharge lamps, a fill bore is provided either through the wall-in the region of the plug-or through a plug, and the fill bore is then closed by a stopper in combination with a melt sealing material, which is so chosen that the sealing material and plug-like member combination provide a minimum of sealing material exposed to the fill in the discharge volume. The fill in the discharge volume of the discharge vessel is ionizable and, for example containing halides, is highly corrosive to the sealing material. The lamp can be made by inserting a stopper into the filling bore, applying, with the stopper in place in the filling bore, sealing material to the outer end of the filling bore, and heating the portion of the discharge vessel to liquefying temperature of the sealing material to liquefy the sealing material and hence close off the fill bore.