Abstract: A mounting member for supporting a shroud, and an arc tube located within such shroud, in an arc discharge lamp is provided. The mounting member includes at least two support clips welded to at least one support rod on the same side of the support rod. A bubble-in-the-press arc lamp is provided having at least one press seal that includes opposite walls. A bubble portion is formed in one wall, and the other wall includes a protrusion. The bubble portion extends towards one wall and the protrusion extends towards the other wall to hold a support clip of a supporting member therebetween. An electric lamp assembly is provided that includes the mounting means and/or the bubble-in-the-press arc tube of the present invention.

Abstract: An hermetically sealed arc tube 14 has a longitudinal axis 60 and contains therewithin an arc generating and sustaining medium, as is known. The ends of the arc tube 14 are sealed with press-seals 43. The seals comprise a substantially parallelepipodonal structure having oppositely disposed, planar sides 56 and 58. A molybdenum foil 50 is sealed in each of the press-seals and is substantially centrally located between the planar sides 56 and 58. An in-lead 52 is secured as by welding to an end of foil 50 and extends outwardly of the arc tube for electrical connection to a source and an electrode 46 is attached to the other end of foil 50 and projects into the arc chamber. A first rod-relief member 62 in the form of a projecting boss 64 is formed on one of the planar sides, for example, 58, and a second rod-relief member 66 in the form of a depression 68 is formed on the other of the planar sides, in this instance side 56.

Abstract: A halide discharge lamp has a an evacuated outer envelope including a getter comprising from about 60 to about 85 percent zirconium, from about 10 to about 20 percent vanadium, and from about 2 to about 10 percent manganese having an activation temperature of less than about 350 degrees Centigrade for reducing the tendency of the lamps to discolor during operation.

Abstract: A bi-metallic switch element 10 has a contact wire 26 attached thereto by means of a plurality of crimps. A first crimp 28 applied at a first pressure fixes the contact wire to the element and a second crimp 30, formed at a lesser, more controlled pressure aligns the contact wire in a predetermined location.

Abstract: An electric lamp assembly includes a sealed lamp envelope, a lamp capsule located within the lamp envelope, a cylindrical, light-transmissive shroud surrounding the lamp capsule, and a mounting arrangement for supporting the lamp capsule and the shroud within the lamp envelope. The mounting arrangement includes one or two supports rods parallel to the axis of the shroud and first and second clips for retaining the shroud and the lamp capsule. The clips prevent both axial and lateral movement of the shroud. The clips are attached to the support rods, typically by welding. In a preferred embodiment, a single clip at each end of the shroud retains both the shroud and the lamp capsule, and requires only a single weld to the support rod.

Abstract: An arc discharge lamp having an arc tube mounted within a lamp envelope includes a thermal switch for controlling application of electrical energy to a starting electrode. The thermal switch is mounted between the arc tube and the lamp base with its longitudinal axis generally parallel to the central axis of the lamp envelope. The thermal switch is spaced from the central axis of the lamp envelope by a support rod and extends into an annular space between the lamp stem and the wall of the lamp envelope. As a result, the maximum temperature of the thermal switch during lamp operation does not exceed about 400.degree. C.

Abstract: An electric lamp assembly includes a sealed lamp envelope, a lamp capsule located within the lamp envelope, a cylindrical, light-transmissive shroud surrounding the lamp capsule, and a mounting arrangement for supporting the lamp capsule and the shroud within the lamp envelope. The mounting arrangement includes one or two supports rods parallel to the axis of the shroud and first and second clips for retaining the shroud and the lamp capsule. The clips prevent both axial and lateral movement of the shroud. The clips are attached to the support rods, typically by welding. In a preferred embodiment, a single clip at each end of the shroud retains both the shroud and the lamp capsule, and requires only a single weld to the support rod.

Abstract: An electric lamp assembly includes a sealed outer envelope, an arc discharge tube mounted within the outer envelope, a safety filament connected in series with the arc discharge tube for extinguishing the arc tube within a predetermined time after the outer envelope is broken, and an electrically-insulating sleeve disposed around the safety filament. The insulating sleeve suppresses emission of electrons from the safety filament and thereby prevents a reduction in frame potential which would increase sodium loss from the arc tube. The insulating sleeve includes openings which permit air to reach the safety filament when the outer envelope is broken. A mounting arrangement includes a pair of mounting tabs which provide electrical connections for the safety filament and which approximately centers the safety filament in the insulating sleeve.

Abstract: A metal halide discharge lamp includes an arc tube having a chemical fill, and a pair of electrodes sealed in the arc tube. The electrodes are tungsten and have differing thoria contents. The electrodes with differing thoria contents provide faster starting times than electrodes with equal low thoria contents and eliminate the electrode meltback, voltage increase and lumen loss that is characteristic of electrodes with equal but higher thoria contents. Preferably, one electrode has a thoria content of about 1.5 to 2 weight percent, and the other electrode has a thoria content of about one weight percent or less.

Abstract: A double-enveloped lamp having a shield surrounding a light-source capsule within a thick-walled outer envelope so that the lamp may be safely operated without necessity of a protective fixture. In the rare event of a burst of the light-source capsule, the shield absorbs and dissipates a portion of the burst energy sufficient to permit the thick-walled outer envelope to remain intact and contain shards and other internal parts within the lamp. In alternate embodiments, the shield may be reinforced, such as with a wire mesh, or the outer envelope may be reinforced, such as with a polymer coating, or both. A thin-walled capsule may be employed in combination with a shield and thick outer envelope. A lamp in accordance with the invention provides the unexpected benefits of improved luminous efficacy and better color rendering characteristics, since the presence of an optimally positioned shield causes the operation of the light-source capsule to be more nearly isothermal.