In the drawings,
FIG. 1 is a perspective view of a sub-assembly according to the invention.
FIG. 2 is a perspective view of the frame member shown in FIG. 1.
FIG. 3 is a perspective view of an alternative sub-assembly according to the invention, provided with a ceramic discharge vessel and a getter.
FIG. 4 is a perspective view of an alternative sub-assembly according to the invention, provided with a ceramic discharge vessel.
FIG. 5 is a schematic view of a PAR lamp comprising a sub-assembly according to the invention.
The sub-assembly shown in FIG. 1 comprises a quartz sleeve 1 and two frame members 2, 3. The frame members are individually supported by the sleeve, which is a strong and stiff isolator. The quartz sleeve has a typical wall thickness of 1.25 mm and a diameter of 19 mm. Each frame member comprises upper-end outer support means 21, 31 and upper-end inner support means 22, 32. The upper-end inner and outer support means 21, 22 and 31, 32 respectively, jointly form a clamping spring, by which each frame member is mounted to the sleeve. The distance between the two legs of the clamping spring is chosen to be such that, in the clamped position, the two legs slightly diverge, thus forcing the sleeve not only against the upper-end outer support, 21, 31 but also into the lower-end inner supports 24, 34, thus providing a vertical fixation of the sleeve. The lower-end inner and outer support means 24, 34 and 23, 33, respectively, form the connection with the lower end of the sleeve. The frame members comprise a finger 25, 35, respectively, for connecting a light source. Each frame member further comprises a support member 26, 36 for mounting in a lamp base.
Details of an embodiment of a frame member are shown in FIG. 2A, wherein the respective parts are denoted by the same reference numerals as in the description of the sub-assembly above. In FIG. 2B, the upper and lower-end outer support means are combined in two outer support means 21 extending along the outer wall of the sleeve. A sub-assembly with the frame members of FIG. 2B is shown in FIG. 3. This sub-assembly further comprises a burner 10 and a getter 38.
FIG. 4 shows another alternative sub-assembly with a burner 10. The main difference with the embodiment shown in FIG. 1 is the shape of the outer support means 21 and 23.
FIG. 5 is a schematic view of a PAR lamp comprising a sub-assembly according to the invention. The arc tube 10 has a cylindrical aluminum oxide envelope with a pair of opposite axial leads 12, 13 extending therefrom, and electrodes (not shown) for maintaining a discharge in the metal halide filling. The arc tube 10 having an upper end 18 and a lower end 20 is mounted between an upper finger 25 and a lower finger 35, both being part of respective frame members 2, 3, which are supported by a quartz sleeve 1. The frame members are preferably formed with stainless steel wire, but Mo, Nb, or Ni may also be used. The sub-assembly further comprises a getter 38.
Other parts of the lamp have a conventional design and include a glass envelope 45 with an aluminized inner surface (PAR), a pair of Ni/Fe ferrules 48 and 49 embedded in the glass, a brass base 50, a center contact 52, and a cover lens 54. The support members 26, 36 of the frame members 2, 3 fit into respective ferrules 48, 49, which in turn are electrically connected to the base 50 and center contact 52.
The lamp is manufactured by welding getter 38 to frame member 3, clamping the frame members 2, 3 onto the sleeve, and welding the arc tube 10 by its axial leads 12, 13 in between the fingers 25 and 35. The support members 26, 36 of the frame members 2, 3 are brazed into respective ferrules 48, 49. The cover 54 is then flame-sealed or glued in place, and a rugged lamp which withstands jarring is obtained.
It should be noted that the foregoing description of embodiments has been given by way of example and that it does not limit the scope of the appending claims.
Patent Application
20080079345
