Reflector lamps

Information

  • Patent Grant
  • 6774545
  • Patent Number
    6,774,545
  • Date Filed
    Thursday, November 9, 2000
    23 years ago
  • Date Issued
    Tuesday, August 10, 2004
    19 years ago
Abstract
A parabolic reflector lamp is provided wherein lamp efficiency is improved by more substantially approximating the shape of a complete parabola at the inner reflective surface. In a first embodiment, the heat shield is placed at the mouth of the opening at the base of the lamp, thereby “filling in” the opening and substantially completing the parabolic shape of the reflector. In a second embodiment, the opening at the base of the lamp is narrowed to minimize its cross-sectional area and maximizing reflective surface area. In a third embodiment, the glass shell of the lamp is provided in a two-piece configuration, allowing the size of the hole through the base of the glass shell to be reduced. The openings required to accommodate electrodes (and an exhaust tube in sealed lamps) are located in a second cup-shaped piece attached via a flange to the main body of the glass shell.
Description




BACKGROUND OF THE INVENTION




This invention relates to reflector lamps. More particularly, it relates to parabolic aluminized reflector lamps.




Parabolic aluminized reflector (PAR) lamps are known in the lighting art. Ideally, a PAR lamp comprises a completely parabolic-shaped glass shell, which is coated with a reflective aluminum substance to form a parabolic reflector. A wire lamp is disposed within the glass shell. A major drawback of this type of lamp is lumen efficiency. A primary reason for the lack of efficiency is that the lamps are not completely parabolic in shape. Instead, the base of the lamp, referred to herein as the “nose chamber” and located at the low point of the parabola, is either completely open or is closed but contains a number of openings. The openings provide portals for connecting electrical leads to the wire lamp, and for an exhaust tube for sealed lamps. Consequently, a significant portion of the base of the parabolic reflector is absent in traditional PAR lamps, thus greatly reducing their efficiently. Because the reflective surface is not a full parabola, some light is either lost in the nose chamber or must be reflected multiple times before it can exit the lamp. Such light loss and multiple reflectivity greatly reduce the efficiency of the lamp.




Thus, it is desired to improve the efficiency of PAR lamps by maximizing the reflective surface of the lamp. It is also desired to improve the efficiency of PAR lamps by modifying the base of the lamp to more completely approximate a parabola, and to minimize the cross-sectional area of the nose portion of the base.




It is also desired to increase the life of PAR lamps by reducing the temperature in the nose chamber.




Finally, it is desired to reduce the risk of short circuit due to contact between the metal leads of the wire lamp and the aluminum reflective coating.




SUMMARY OF THE INVENTION




A first embodiment of a reflector lamp is provided comprising a glass shell that has a concave inner surface, an outer surface, and an opening through the base of the glass shell forming a nose portion thereof. The reflector lamp also comprises a reflective coating on the concave inner surface, a wire lamp within the shell, and a heat shield in the mouth of the opening in the base of the glass shell, substantially completing the shape of the concave inner surface.




A second embodiment of a reflector lamp is provided comprising a base, a wire lamp, and a glass shell that has a concave inner surface, an outer surface, and a reflective coating on the inner surface. The glass shell further comprises a bottom having an opening therein, which opening forms the top of a slot disposed within the base. The slot has a major diameter and a minor diameter such that the major diameter is substantially longer than the minor diameter. The wire lamp is disposed within the glass shell, and extends into the slot. A third embodiment of a reflector lamp is provided comprising a glass shell, a wire lamp, and a flange, wherein the glass shell has a concave inner surface, an outer surface, and a reflective coating disposed on the inner surface. A wire lamp is disposed within the glass shell. The flange extends from the outer surface of the glass shell and defines a perimeter of a chamber. An extension of the glass shell extends over the chamber defined by the flange. The extension of the glass shell has an inner surface coated with the reflective coating, and an opening therethrough in communication with the chamber defined by the flange.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a cross-sectional view of a prior art parabolic reflector lamp.





FIG. 2

is a cross-sectional view of a first embodiment of a parabolic reflector lamp of the present invention taken along line


2





2


of FIG.


3


.





FIG. 3

is a top view of the lamp of FIG.


2


.





FIG. 4

is a cross-sectional view of a prior art parabolic reflector lamp taken along


4





4


of

FIG. 5

, including a wire lamp.





FIG. 5

is a top view of the parabolic reflector lamp of

FIG. 4

but not including a wire lamp.





FIG. 6

is a cross-sectional view of a second embodiment of a parabolic reflector lamp of the present invention, including a wire lamp, taken along line


6





6


of FIG.


8


.





FIG. 7

is a cross-sectional view of the lamp of

FIG. 6

, taken along line


7





7


of FIG.


8


.





FIG. 8

is a top view of the lamp of

FIG. 6

, but not including a wire lamp.





FIG. 9

is a bottom view of the lamp of FIG.


6


.





FIG. 10

is an exploded perspective view of a third embodiment of a parabolic reflector lamp of the present invention.





FIG. 11

is a cross-sectional view of a glass shell of the lamp of

FIG. 10

taken along line


11





11


of

FIG. 12

, including a wire lamp.





FIG. 12

is a top view of the glass shell of

FIG. 10

, not including a wire lamp.





FIG. 13

is a bottom view of the glass shell of FIG.


10


.





FIG. 14

is a cross-sectional view of the glass cup of

FIG. 10

, taken along line


14





14


of FIG.


15


.





FIG. 15

is a top view of the glass cup of FIG.


10


.





FIG. 16

is a cross-sectional view of a preferred embodiment of the parabolic reflector lamp according to the present invention.





FIG. 17

is a top view of a parabolic reflector lamp having three holes through a base thereof, with one of the three holes offset from center to accommodate minimizing the diameter of the base according to a preferred embodiment of the present invention.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS




In the description that follows, when a preferred range, such as 5 to 25 (or 5-25) is given, this means preferably at least 5, and separately and independently, preferably not more than 25.




“Lumen efficiency” as used herein means the ratio of lumen output from a PAR lamp to the total lumens generated by the wire lamp within the PAR lamp. Simply, it is the ratio of lumen output to total generated lumens.





FIG. 1

shows a traditional PAR lamp


10


comprising a substantially parabolic glass shell


12


having an inner surface


13


with a reflective coating


14


disposed thereon, an outer surface


15


, a wire lamp


36


which is well known in the art, and a heat shield


18


. The reflective coating


14


typically comprises aluminum, though the reflective coating


14


can also comprise silver, gold, white gold, chromium or any other suitable reflective material. The glass shell


12


has an opening at its bottom to which is attached or formed a base


86


which defines a nose chamber


22


. The electrical leads


70


,


72


to the wire lamp


36


are shown in

FIGS. 1 and 2

. The nose chamber


22


has a mouth


26


located adjacent the base of the parabola. The heat shield


18


prevents heat from radiating from the wire lamp


36


to the nose chamber


22


. Without the heat shield


18


, the nose chamber


22


is exposed to higher temperatures within, thereby reducing the functional life of the lamp


10


.




The heat shield


18


comprises any material sufficiently reflective of both of infrared (IR) radiation (to minimize radiant heating of the nose chamber


22


), and visible light (to improve the efficiency of the lamp


10


); e.g. stainless steel, or, more preferably, a silicon-coated silver layer deposited on a disk substrate. In the traditional lamp arrangement shown in

FIG. 1

the heat shield


18


is located immediately below the light-emitting portion of the wire lamp


36


. The efficiency of the lamp


10


is low with the heat shield


18


in this position because a large portion of light emitted from the wire lamp


36


is reflected off the lower-reflectivity heat shield and this portion of light bounces more than once before leaving the PAR lamp, as illustrated in FIG.


1


. Each reflection results in approximately a 15% loss in lumens. Moving the heat shield


18


to a position where it substantially completes the parabola significantly reduces multiple reflectivity as shown in

FIG. 2

, and reduces the amount of light hitting the heat shield. As multiple reflections are eliminated, the overall efficiency of the lamp


10


is increased.




In the embodiment of the invention shown in

FIGS. 2 and 3

, the efficiency of the lamp


10


is increased by changing the location of the heat shield


18


so that it is substantially within or adjacent the nose chamber


22


. The heat shield


18


is moved from its position immediately adjacent the bulb


37


of wire lamp


36


to a position where it rests preferably even with the mouth


26


of the nose chamber


22


. In its new position, the heat shield


18


“fills in” the mouth


26


of the nose chamber


22


, substantially completing the parabolic reflector. The top surface


85


of the heat shield


18


preferably forms a continuation or substantial continuation of the top or inner surface


80


of reflective coating


14


. In addition to maximizing the optical efficiency of the lamp, placing the heat shield within mouth


26


, immediately adjacent to


81


,


82


, minimizes heating of the nose chamber, and is thus the optimum position for thermal function of the heat shield.




As will be understood by one skilled in the art, PAR lamps of the sort contemplated in the present invention normally operate in an inverted position; that is, with the open end of the parabolic reflector facing downward from a ceiling toward a floor below, and the nose portion screwed into a light fixture contained in the ceiling via a threaded connection as is well known in the art. (See FIG.


16


).




During operation, the hottest part of the lamp is the bulb portion


37


of the wire lamp


36


. As air adjacent the bulb portion


37


is heated, its density is decreased. This low-density heated air rises through the surrounding cooler air of lower density, and impacts the heat shield


18


. With the heat shield in its most preferred position, in the mouth


26


of the nose chamber


22


such that its top surface


85


substantially completes the parabola, the hot air flows naturally along the curvature of the parabola following a circular convective path


38


as shown in FIG.


16


. In this manner, heated air is prevented from entering the nose chamber in the most efficient manner possible.




With the heat shield in its optimum position as described above, the area of the open annulus


39


between the edge of the heat shield and the edges


81


,


82


of coating


14


(also the edges of mouth


26


) is minimized. Preferably, the heat shield has a diameter such that the width of the open annulus


39


is no greater than 2, preferably 1.5, preferably 1, preferably 0.9, preferably 0.8, preferably 0.7, preferably 0.6, preferably 0.5, mm.




Less preferably, the heat shield


18


can be placed slightly above or slightly below its optimum position, for example, within 5, preferably 4, preferably 3, preferably 2, preferably 1.5, preferably 1, mm above or below mouth


26


. The heat shield


18


may, for example, may be placed in the cylinder having a top at


81


,


82


and a bottom at


83


(the cylinder thus having a height substantially equal to the thickness of the coating


14


and glass shell


12


combined). In this case, it is preferred that the heat shield


16


is placed in the top half of the cylinder just defined, that is, in the cylinder having a top at


81


,


82


and a bottom at


84


, which is approximately the midpoint of the thickness of the glass shell


12


. Less preferably, the heat shield


18


can be placed slightly beneath the shell


12


, that is, below location


83


. Less preferably, the heat shield can be placed slightly above (within 1 or 2 mm above) the coating


14


. However, it should be noted that, in placing the heat shield in one of these less preferred positions, both thermal and optical efficiency of the heat shield decrease. The negative optical effects have already been discussed. By locating the heat shield in a recessed position within the nose chamber


22


, a cavity is created between the edges


81


,


82


(refer to

FIG. 1

) and the heat shield within which air cannot circulate. This dead space creates a pocket of stagnant hot air, thus significantly increasing the temperature of the nose portion, thereby defeating the function of the heat shield. Conversely, by placing the heat shield above the edges


81


,


82


, the space between the heat shield


18


and the edges


81


,


82


is increased, thus providing a larger portal through which hot air may be convected into the nose chamber


22


, again defeating the function of the heat shield.




Optionally, the heat shield


18


can be provided in a concave curved-shape to more closely approximate the parabolic shape of the reflective coating


14


. It should be noted that when in its optimum position, the heat shield


18


has a slightly smaller diameter than the mouth


26


of the nose chamber


22


so as not to contact the reflective coating


14


, thereby increasing the risk of short-circuiting the electrical leads


70


,


72


. By moving the heat shield


18


to the mouth


26


of the nose chamber


22


, the overall efficiency of the lamp


10


is increased from approximately 70% to 80%.




In its optimum position adjacent edges


81


,


82


, the heat shield


18


further serves its primary function of reducing the temperature of the nose chamber


22


because the IR-reflecting material of the heat shield reflects the IR radiation out of the lamp, away from the nose chamber


22


. Thus, the IR radiation does not enter the nose chamber


22


and, in turn, the temperature in the nose chamber


22


is reduced leading to longer lamp life.




In a second preferred embodiment of the invention, the efficiency of the lamp is increased by a new shape of the glass shell


12


onto which is deposited the reflective coating


14


. A second type of traditional PAR lamp is illustrated in

FIGS. 4 and 5

, wherein a nose chamber


34


comprises a secondary parabola


30


and a closed circular base


28


having holes or openings


52


,


54


, for an exhaust tube (not shown) and ferrules (not shown) that provide conduits for connecting the electrical leads


70


,


72


from the wire lamp


36


to a screw base (not shown). As can be seen in

FIG. 4

, the secondary parabola


30


of this second type of traditional PAR lamp subtends the primary parabolic reflector, and together with it forms a substantially conically shaped reflector about the filament of the wire lamp


36


. Light incident to the secondary parabola


30


near the base thereof is either absorbed by the interior surface of the nose chamber


34


, or is multiply reflected prior to being directed toward the opening of the lamp


10


. Furthermore, some second-reflected light will be blocked from exiting the lamp


10


by the wire lamp


36


.




To solve this problem, the shape of the nose chamber


34


is modified according to a second preferred embodiment of the present invention wherein the relatively wide circular opening of the nose chamber


34


is reduced to a relatively narrow slot or opening


40


as illustrated in

FIGS. 6-8

, eliminating the secondary parabola


30


. The slot has a major diameter and a minor diameter, wherein the major diameter is 1.5, preferably 2, preferably 3, preferably 4, preferably 5, (though typically 4), times longer than the minor diameter thereof. The minor diameter of the slot


40


is only wide enough to accommodate the wire lamp


36


and electrical leads


70


,


72


, and has at its base a plurality of openings


52


,


54


to accommodate ferrules (not shown) through which the electrical leads


70


,


72


pass, and an exhaust tube (also not shown). Preferably three openings


52


,


54


are provided, less preferably one, two, or more than three openings, which extend through the inner surface


13


and the outer surface


15


at the bottom of the slot


40


. The slot


40


can be any shape that will accommodate the wire lamp


36


and electrical leads


70


,


72


. Preferably, the slot


40


is substantially rectangular or, if fabricating a rectangle is costly, the corners can be rounded so the slot


40


has a substantially elliptical shape when viewed from above. By narrowing the nose chamber


34


, the lamp more closely approximates the desired parabolic shape, and the efficiency of the lamp is increased while leaving sufficient area to accommodate openings


52


,


54


.




However, narrowing the nose chamber


34


without changing the shape of the exterior of the base


32


leads to a high volume of glass in the base


32


of the lamp


10


. When the glass for the lamp


10


is shaped and cooled, it is important that the glass throughout the lamp cools at the same rate. When portions of the glass cool at different rates, the glass can deform and lose its shape. Increased glass volume leads to an uneven cooling rate at the base


32


, and thus, the base


32


deforms upon cooling.




This problem is solved by eliminating the excess glass in the outer portion of the base


32


. Specifically, the shape of the outside of the base


32


is modified according to the present invention from circular to substantially cross-shaped. The base


32


need not be perfectly cross-shaped as shown in FIG.


9


. The corners of the cross may be rounded for ease of fabrication. The cross-shape eliminates excess glass volume in the base


32


that otherwise would contribute to uneven cooling during the forming process.




Compared to the lamp design of the prior art (as illustrated in FIGS.


4


and


5


), a lamp


10


of the present invention (as illustrated in

FIGS. 6-9

) has a much narrower opening at the parabolic reflector for a lamp of the same size. It should be noted that the exact dimensions of the slot


40


will depend on the size of the lamp


10


.




Optionally, the relatively large diameters of both the nose chamber


34


and closed circular base


28


thereof (typically about 1.1 inches) as seen in

FIG. 5

can be narrowed in the following manner. In traditional PAR lamps as illustrated in

FIGS. 4-5

, a wide base


28


was necessary to accommodate openings


52


,


54


for electrical leads


70


,


72


and an exhaust tube


58


as explained above. However, the diameter of the nose chamber


34


and base


28


of the PAR lamp may be reduced by moving opening


54


from its central position as shown in

FIG. 5

to a new offset position as shown in FIG.


17


. In this embodiment, the opening


54


preferably is positioned offset from center such that the diameter of the nose chamber


34


(and base


28


) is no greater than 1, preferably 0.95, preferably 0.90, preferably 0.85, preferably 0.82, inches. The opening


54


is preferably offset from center of base


28


such that the distance from the center of


54


to the center of


52


is no less than 6, more preferably 7, more preferably 8, more preferably 9, more preferably 10, more preferably 11, mm. It is believed that by reducing the diameter of the nose chamber


34


and base


28


in this manner, lumen efficiency can be improved from about 70%, typical of the prior art, to approximately 80%.




In a third embodiment of the invention, the efficiency of the lamp


10


is increased by making the shape of the glass shell


12


more closely approximate a parabola. In this embodiment, glass shell


12


is formed as two pieces instead of a single piece. As discussed above in conjunction with a previous embodiment, in traditional PAR lamps (as illustrated in

FIGS. 4 and 5

) the base


32


contains a nose chamber


34


having holes


52


,


54


at its base to accommodate an exhaust tube and ferrules. This configuration results in inefficiency because the nose chamber


34


subtends to a substantially linear acute angle about the filament of the wire lamp


36


. Light incident to the nose chamber


34


is either absorbed by the interior surface thereof, or requires multiple reflections before being directed toward the opening of the reflector. Furthermore, some second-reflected light will be blocked by the wire lamp


36


.




To alleviate this problem in the present embodiment (shown in FIGS.


10


-


15


), a plurality of holes or openings


52


,


54


, preferably three openings


52


,


54


, less preferably one, two, or more than three openings, (to accommodate ferrules


56


and exhaust tube


58


) are disposed in the base


76


of a glass cup


60


. The glass cup has a perimeter wall


78


attached to and extending upward from the base


76


, which, when the lamp


10


is fully assembled, is permanently attached to a flange


62


formed integrally with and extending downward from the base


64


of the lamp


10


, defining a perimeter of a chamber


74


. Preferably, the cup


60


and flange


62


are of equivalent diameter such that the top edge of perimeter wall


78


engages the bottom edge of flange


62


in the final assembled position. Less preferably, the cup


60


is sized such that its perimeter wall


78


slides into the chamber


74


defined by flange


62


in the final assembled position. Preferably, the glass cup


60


and flange


62


both have circular cross-sections, though any suitable shape may be used.




The perimeter wall


78


of the glass cup


60


is attached to the flange


62


by any means known in the art. Suitable means include fusing, clamping and the use of o-rings. Preferably, the glass cup


60


is connected to the flange


62


by fritting, wherein frit glass is applied to the flange


62


, or alternatively, to the glass cup


60


, and the frit glass is heated slightly above its melting temperature (which is less than that of the glass used to make the glass cup


60


and flange


62


) with both components in their final assembled position. The frit glass is allowed to cool, wherein it solidifies, thus joining the flange


62


and glass cup


60


.




As illustrated in

FIGS. 10-13

, the base


64


now has only a small key-shaped hole or opening


66


that is large enough to allow the wire lamp


36


and one of its electrical leads


70


to pass through. The second lead


72


does not pass through the key-shaped hole


66


. Because the base


76


of the glass cup


60


does not have a reflective coating, the chance of a short-circuit resulting from both electrical leads


70


,


72


contacting a metallic reflective coating is reduced.




The key-shaped hole or opening


66


may be of any shape that minimizes the size of the opening, yet is large enough for a wire lamp


36


and electrical lead


70


to pass through. Preferably, the opening


66


is key-shaped, i.e. having a substantially circular portion


67


with a substantially rectangular portion


69


extending therefrom (as best shown in FIG.


12


). In this manner, the parabolic reflector has the maximum possible surface area while still providing an opening to accommodate the wire lamp


36


and electrical lead


70


. This design is particularly effective because the interior reflective surface of the parabolic reflector has an extension or extension flange or overhang portion


87


that overhangs the chamber


74


defined by flange


62


as best seen in FIG.


11


. Also, as shown in

FIGS. 10 and 11

, the extension


87


has an opening therethrough in fluid communication with the chamber


74


to accommodate the wire lamp


36


and electrical lead


70


. This represents a significant improvement in reflective surface area over the prior art as illustrated in

FIG. 4

, because at least 20, preferably 30, preferably 40, preferably 50, preferably 60, preferably 70, preferably 80, preferably 90, percent of the open space over the nose chamber


34


of the prior art has been replaced in the present embodiment by additional parabolic reflective surface on the extension or overhang portion


87


.




The base


76


of the glass cup


60


has a plurality of holes


52


and


54


, typically three holes, extending therethrough. Ferrules


56


are disposed within the holes


52


such that the ferrules


56


provide sealed contact means for connecting the electrical leads


70


and


72


of the wire lamp


36


to the screw base. An exhaust tube


58


is fused to a hole


54


in the base


76


of the glass cup


60


. In this manner, the wire lamp


36


may be evacuated, filled with inert gas, and the exhaust tube sealed by “pinching” the end as is known in the art once the glass cup


60


has been attached to the flange


62


.




While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.



Claims
  • 1. A reflector lamp comprising a glass shell, a base, a wire lamp, and a heat shield, said wire lamp being disposed within said glass shell, said glass shell having a concave inner surface and an outer surface, said glass shell having a thickness, said glass shell having a reflective coating disposed on said inner surface, said glass shell having a bottom, said glass shell having an opening at said bottom, said base extending from said bottom of said glass shell, said opening and said base defining a nose chamber, said heat shield being disposed substantially within or adjacent said nose chamber, said nose chamber having a sealed-off exhaust hole in a base of said nose chamber, said sealed-off exhaust hole being substantially offset from a center of said base of said nose chamber, said base of said nose chamber having a diameter of no greater than 1 inch.
  • 2. A reflector lamp according to claim 1, wherein said concave inner surface is substantially parabolic.
  • 3. A reflector lamp according to claim 2, wherein said heat shield is positioned so as to substantially complete said parabolic inner surface.
  • 4. A reflector lamp according to claim 1, wherein said heat shield is a concave curved-shape.
  • 5. A reflector lamp according to claim 1, wherein said heat shield comprises stainless steel.
  • 6. A reflector lamp according to claim 1, wherein said heat shield comprises a substrate and a reflective coating disposed on said substrate.
  • 7. A reflector lamp according to claim 6, said reflective coating on said substrate comprising chromium.
  • 8. A reflector lamp according to claim 1, wherein said nose chamber has a plurality of sealed-off holes disposed in said base of said nose chamber.
  • 9. A reflector lamp according to claim 8, wherein the number of said sealed-off holes is three.
  • 10. A reflector lamp according to claim 1, wherein said base of said nose chamber has a diameter of no greater than 0.90 inches.
  • 11. A reflector lamp according to claim 1, wherein said base of said nose chamber has a diameter of no greater than 0.85 inches.
  • 12. A reflector lamp according to claim 1, wherein said base of said nose chamber has a diameter of no greater than 0.82 inches.
  • 13. A reflector lamp according to claim 1, wherein said heat shield is positioned above said opening at said bottom of said glass shell within 4 mm thereof.
  • 14. A reflector lamp according to claim 1, wherein said heat shield is positioned below said opening at said bottom of said glass shell within 4 mm thereof.
  • 15. A finished reflector lamp comprising a glass shell, a base, and a wire lamp, said wire lamp being disposed within said shell, said glass shell having a concave inner surface and an outer surface, said glass shell having a thickness, said glass shell having a reflective coating disposed on said inner surface, said glass shell having a bottom, said glass shell having an opening at said bottom, said base extending from said bottom of said glass shell, said opening and said base defining a nose chamber, said nose chamber having a bottom and having a perimeter wall having an inner surface, said perimeter wall and said nose chamber bottom defining a volume inside said nose chamber, said nose chamber defining a slot having a major dimension and a minor dimension, said major dimension being substantially longer than said minor dimension, said wire lamp extending into said slot, substantially all of the perimeter wall inner surface being in fluid communication with the volume inside said nose chamber.
  • 16. A reflector lamp as in claim 15, wherein said slot has a substantially rectangular cross-section.
  • 17. A reflector lamp as in claim 15, wherein said slot has a substantially elliptical cross-section.
  • 18. A reflector lamp according to claim 15, said major dimension being longer than said minor dimension by a factor selected from the group consisting of 1.5, 2, 3, 4, and 5.
  • 19. A reflector lamp according to claim 15, said major dimension being 4 times longer than said minor dimension.
  • 20. The reflector lamp according to claim 15, wherein the minor dimension of said nose chamber is less than one inch.
  • 21. A reflector lamp comprising a glass shell, a base, and a wire lamp, said wire lamp being disposed within said shell, said glass shell having a concave inner surface and an outer surface, said glass shell having a thickness, said glass shell having a reflective coating disposed on said inner surface, said glass shell having a bottom, said glass shell having an opening at said bottom, said base extending from said bottom of said glass shell, said opening and said base defining a nose chamber, said nose chamber having an inner surface and a bottom said nose chamber defining a slot having a major dimension and a minor dimension, said major dimension being substantially longer than said minor dimension, said wire lamp extending into said slot, said base having a bottom, the bottom of said base of said lamp having a substantially cross-shaped cross-section.
  • 22. A reflector lamp comprising a glass shell, a wire lamp, and a flange, said wire lamp being disposed within said glass shell, said glass shell having a concave inner surface and an outer surface, said glass shelf having a reflective coating disposed on said concave inner surface, said flange extending from said outer surface of said glass shell and defining a perimeter of a chamber, an inwardly extending overhang portion of said glass shell extending over said chamber and being substantially continuous with said glass shell, said overhang portion having an inner surface coated with said reflective coating, said overhang portion having an opening therethrough in communication with said chamber, said opening having a longitudinal dimension along a longitudinal axis and a lateral dimension along a lateral axis, said longitudinal dimension being longer than said lateral dimension.
  • 23. A reflector lamp according to claim 22, further comprising a glass cup attached to said flange extending from said outer surface of said glass shell, said glass cup comprising a base, a wall extending from said base of said glass cup at a perimeter thereof, and a plurality of sealed openings on said base of said glass cup.
  • 24. A reflector lamp according to claim 23, said wall of said glass cup and said flange extending from said glass shell having substantially the same diameter, said wall of said glass cup being permanently attached to said extending flange by glass flitting.
  • 25. A reflector lamp according to claim 22, wherein said flange is integrally formed as part of said glass shell.
  • 26. The reflector lamp of claim 22, wherein said opening is a key-shaped hole.
  • 27. The reflector lamp of claim 22, wherein said overhang portion covers at least 50% of the space over said chamber.
  • 28. The reflector lamp of claim 22, wherein said overhang portion covers at least 80% of the space over said chamber.
  • 29. The reflector lamp of claim 26, wherein said overhang portion covers at least 70% over said chamber.
  • 30. A reflector lamp comprising a glass shell, a base, and a wire lamp, said wire lamp being disposed within said shell, said glass shell having a concave inner surface and an outer surface, said glass shell having a thickness, said glass shell having a reflective coating disposed on said inner surface, said glass shell having a bottom, said glass shell having an opening at said bottom, said base extending from said bottom of said glass shell, said opening and said base defining a nose chamber, said nose chamber having a bottom and having a perimeter wall having an inner surface, said nose chamber defining a slot having a major dimension and a minor dimension, said major dimension being substantially longer than said minor dimension, said wire lamp extending into said slot, said nose chamber having a reflective coating disposed on said inner surface of said perimeter wall of said nose chamber effective to reflect light emitted by said wire lamp.
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