Title of Invention

RE-ENTRANT CAVITY FLUORESCENT LAMP SYSTEM

Abstract An electrodeless fluorescent lamp (10) having a burner (20), a ballast housing (30) containing a ballast (40) and a screw base (50) for connection to a power supply. A reentrant cavity (60) is formed in the burner (20) and an amalgam receptacle (70) containing amalgam (75) is formed as a part of the reentrant portion and in communication with the burner (20). A housing cap (80), formed of a suitable plastic, connects the burner (20) to the ballast housing (30) and a suitable adhesive (31) fixes the burner to the housing cap (80). An EMI cup (90) is formed as an insert to fit into the ballast housing (30), which also is formed of a suitable plastic, and has a bottom portion (100) and an EMI cap (110) with an aperture (120) therein closing an upper portion (140). The EMI cup (90) and the EMI cap (110) are preferably formed from 0.5 mm brass. The amalgam receptacle (70) extends through the aperture (120) and into the cup (90). For a fixed amalgam position, changing the aperture size allows adjustment of the amalgam tip temperature, and thus, allows control of the system lumen output, efficacy, CCT and CR.I, all of which are dependent on the amalgam temperature.
Full Text RE-ENTRANT CAVITY FLUORESCENT LAMP SYSTEM
001. CROSS REFERENCE TO RELATED APPLICATIONS
002. This application claims priority from Provisional Patent Application No. 60/519,143 filed
November 12,2003.
003. TECHNICAL FIELD
004. This invention relates to fluorescent lamps and more particularly to electrodeless
005. BACKGROUND ART
006. As market forces call for more efficient fluorescent lamps to be smaller and more
incandescent in shape, conventional electroded fluorescent lamp faces difficult hurdles.
The A-shaped bulb that covers conventional electroded discharges causes an
approximately 8% lumen decrease due to reflection loss. The gas separation between the
electroded lamp's tubular phosphor layer (where the heat is generated) and the A-shaped
outer covering (where heat escapes the system) leads to inherently higher system
temperatures. Higher temperatures lead to significant problems in producing higher
lumen (e.g., >15W, 800 lumen), A-shaped electroded systems.
007. Electrodeless fluorescent discharge lamps have solved many of the problems associated
with the previous attempts to market compact fluorescent lamps. The discharge chamber
can be made in the A-shape so there is no need for an outer covering. The phosphor is on
the A-shape portion of the lamp so cooling is more effective. Such compact electrodeless
lamps have been on the market for some time and basically comprise two different types;
one type being an inductively driven plasma discharge with a separate ballast; and the
other being an integrally ballasted, inductively driven discharge. The latter type of
electrodeless discharge lamp works well generally; however, it presents some problems
with heat, inadequate RF shielding for some uses, and inadequate temperature control for
the amalgam.
008. DISCLOSURE OF INVENTION
009. It is, therefore, an object of the invention to obviate the disadvantages of the prior art.
0010. It is another object of the invention to enhance the operation of electrodeless fluorescent
lamps.
0011. Yet another object of the invention is a fluorescent lamp having better amalgam
temperature control.
0012. Still another object of the invention is the provision of an electrodeless fluorescent lamp
with good RF shielding at a reasonable cost.
0013. These objects are accomplished, in one aspect of the invention, by the provision of an
electrodeless fluorescent lamp having a burner, a ballast housing containing a ballast and
a base for connection to a power supply. A reentrant cavity is provided in the burner and
an amalgam receptacle is in communication with the burner. A housing cap connects the
burner to the ballast housing and there is an EMI cup formed as part of the ballast
housing. The EMI cup has a bottom portion and a cap with an aperture therein closing an
upper portion. The amalgam receptacle extends through the aperture and into the ballast
housing, which helps to regulate the amalgam temperature. The ballast housing provides
superior RF shielding allowing multiple uses of the lamp in places previously
unavailable.
0014. BRIEF DESCRIPTION OF THE ACCOMPANYING DRA WINGS
0015. Fig. I is an elevationai view of an embodiment of the invention, partially in section; and
0016. Fig. 2 is an enlarged sectional view of the ballast housing of the invention.
0017. BEST MODE FOR CARRYING OUT THE INVENTION
0018. For a better understanding of the present invention, together with other and further
objects, advantages and capabilities thereof, reference is made to the following disclosure
and appended claims in conjunction with the above-described drawings.
0019. Referring now to the drawings with greater particularity, there is shown in Fig. 1 an
electrodeless fluorescent lamp 10 having a burner 20, a ballast housing 30 containing a
ballast 40 and a screw base 50 for connection to a power supply. A reentrant cavity 60 is
formed in the burner 20 and an amalgam receptacle 70 containing amalgam 75 is formed
as a part of the reentrant portion and in communication with the burner 20. A housing
cap 80, formed of a suitable plastic, connects the burner 20 to the ballast housing 30 and a
suitable adhesive 3 1 fixes the burner to the housing cap 80. An EMI cup 90 is formed as
an insert to fit into the ballast housing 30, which also is formed of a suitable plastic, and
has a bottom portion 100 and an EMI cap 110 with an aperture 120 therein closing an
upper portion 140. The EMI cup 90 and the EMI cap 110 are preferably formed from 0.5
mm brass. The amalgam receptacle 70 extends through the aperture 120 and into the cup
90. For a fixed amalgam position, changing the aperture size allows adjustment of the
amalgam tip temperature, and thus, allows control of the system lumen output, efficacy,
CCT and CRI, all of which are dependent on the amalgam temperature.
0020. A coupler in the form of a wire-wrapped a ferrite tube 150 is positioned in the reentrant
cavity 60 and includes a thermally insulating coupler cap 152 and a coupler base 154
formed of ceramic paper containing high purity alumina based refractory fibers, such as
Rescor 300 available from Cotronics Corporation. Kapton tape may be used to secure the
wire wrapping at the top and bottom of the ferrite core. A burner housing insulation 155
is fitted into the reentrant portion and also serves to support the ferrite core. Housing
insulation 155 is preferably made from black nylon. A flange 156 centers the housing
insulation 155 within the ballast housing 30.
0021. The EMI cup 90 contains a ballast board 160 containing ballast components 170, and the
ballast board is positioned adjacent the bottom portion 100 of the cup 90 and a gasket 180
is positioned adjacent the upper portion 140 of the cup 90 and against the cap 110. The
gasket 180 holds the ballast board 160 in place and provides cushioning for axial shocks
to the lamp 10. The gasket 180 is preferably constructed of silicone foam rubber.
0022. The EMI cup 90 additionally contains an annular centering ring 190 that is preferably
formed from nylon and that surrounds the ballast board 160 and includes an inwardly
extending flange 200 upon which the ballast board 160 rests for maintaining a fixed
distance between a bottom 210 of the ballast board 160 and the bottom portion 100 of the
EMI cup 90.
0023. The EMI cup 90 also contains a ballast heat sink 220 that is applied in a viscous state to
encompass surface mount components on the bottom 210 of the ballast board 160.
whereby both electrical isolation and thermal contact are formed to provide cooling of the
ballast 40 on the ballast board 160. In a preferred embodiment of the invention the ballast
heat sink is comprised of a thermally conductive epoxy and 5 to 6 grams of Sylgard 165,
available from Dow Corning.
0024. A DC board 230 can be positioned in the screw base 50 and is insulated from the EMI
cup 90 by an insulating disc 235 of, preferably, Nomex, about 0.005 inches thick.
0025. Apertures, such as 240 in the EMI cap 1 10 and 241 in the bottom 100 of EMI cup 90, are
provided to allow the threading of the necessary connecting wires.
0026. There is thus provided an electrodeless fluorescent lamp having minimal interference
with nearby electrical appliances due to its RF shielding and with excellent amalgam
temperature control.
0027. While there have been shown and described what are at present considered to be the
preferred embodiments of the invention, it will be apparent to those skilled in the art that
various changes and modification can be made herein without departing from the scope of
the invention as defined by the appended claims.
WE CLAIM:
1. Electrodeless fluorescent lamp with re-entrant cavity having a burner, a ballast housing
containing a ballast and a base for connection to a power supply, further comprising:
a reentrant cavity in said burner;
an amalgam receptacle in communication with said burner;
a housing cap connecting said burner to said ballast housing;
an Electro Magnetic Interference (EMI) cup formed as part of said ballast housing, said
EMI cup having a bottom portion and having a cap with an aperture therein closing an
upper portion, said amalgam receptacle extending through said aperture and into said
ballast housing; a ferrite tube is positioned in said reentrant cavity characterized in that
said EMI cup contains a ballast board containing ballast components, said ballast board
being positioned adjacent said bottom portion and a gasket positioned adjacent said upper
portion and said gasket holding said ballast board in place and providing cushioning for
axial shocks to said lamp.
2. The electrodeless fluorescent lamp of claim 1 wherein said EMI cup contains an annular
centering ring surrounding said ballast board and including an inwardly extending flange
upon which said ballast board rests for maintaining a fixed distance between a bottom of
said ballast board and said bottom portion of said EMI cup.
3. The electrodeless fluorescent lamp of claim 1 or 2 wherein said EMI cup contains a
ballast heat sink in a viscous state to encompass surface mount components on said
bottom of said ballast board whereby electrical isolation and thermal contact are formed
to provide cooling of the ballast on said ballast board.


An electrodeless fluorescent lamp (10) having a burner (20), a ballast housing (30) containing a
ballast (40) and a screw base (50) for connection to a power supply. A reentrant cavity (60) is
formed in the burner (20) and an amalgam receptacle (70) containing amalgam (75) is formed as
a part of the reentrant portion and in communication with the burner (20). A housing cap (80),
formed of a suitable plastic, connects the burner (20) to the ballast housing (30) and a suitable
adhesive (31) fixes the burner to the housing cap (80). An EMI cup (90) is formed as an insert to
fit into the ballast housing (30), which also is formed of a suitable plastic, and has a bottom
portion (100) and an EMI cap (110) with an aperture (120) therein closing an upper portion
(140). The EMI cup (90) and the EMI cap (110) are preferably formed from 0.5 mm brass. The
amalgam receptacle (70) extends through the aperture (120) and into the cup (90). For a fixed
amalgam position, changing the aperture size allows adjustment of the amalgam tip temperature,
and thus, allows control of the system lumen output, efficacy, CCT and CR.I, all of which are
dependent on the amalgam temperature.

Documents:

679-KOL-2004-(28-10-2011)-CORRESPONDENCE.pdf

679-KOL-2004-(28-10-2011)-OTHER PATENT DOCUMENTS.pdf

679-KOL-2004-(28-10-2011)-PA.pdf

679-kol-2004-abstract.pdf

679-kol-2004-claims.pdf

679-kol-2004-correspondence.pdf

679-kol-2004-description (complete).pdf

679-kol-2004-drawings.pdf

679-kol-2004-examination report.pdf

679-kol-2004-form 1.pdf

679-kol-2004-form 18.pdf

679-kol-2004-form 2.pdf

679-kol-2004-form 26.pdf

679-kol-2004-form 3.pdf

679-kol-2004-form 5.pdf

679-kol-2004-granted-abstract.pdf

679-kol-2004-granted-claims.pdf

679-kol-2004-granted-correspondence.pdf

679-kol-2004-granted-description (complete).pdf

679-kol-2004-granted-drawings.pdf

679-kol-2004-granted-examination report.pdf

679-kol-2004-granted-form 1.pdf

679-kol-2004-granted-form 18.pdf

679-kol-2004-granted-form 2.pdf

679-kol-2004-granted-form 26.pdf

679-kol-2004-granted-form 3.pdf

679-kol-2004-granted-form 5.pdf

679-kol-2004-granted-priority document.pdf

679-kol-2004-granted-reply to examination report.pdf

679-kol-2004-granted-specification.pdf

679-kol-2004-reply to examination report.pdf

679-kol-2004-specification.pdf


Patent Number 237809
Indian Patent Application Number 679/KOL/2004
PG Journal Number 02/2010
Publication Date 08-Jan-2010
Grant Date 07-Jan-2010
Date of Filing 01-Nov-2004
Name of Patentee OSRAM SYLVANIA INC.
Applicant Address 100 ENDICOTT STREET, 01923 DANVERS, MA
Inventors:
# Inventor's Name Inventor's Address
1 BENJAMIN ALEXANDROVICH 14 GIBBS STR #1 02146 BROOKLINE, MA
2 R. KENNETH HUTCHERSON 19 STURTVANT STREET 01915 BEVERLY, MA
3 ALEXANDER A. SAPOZHNIKOV 49 WILSON PLACE 01701 FRAMINGHAM, MA
4 VALERY-ANTON GODYAK 367 HARVARD ST. #2 02146 BROOKLINE MA
PCT International Classification Number H01J 65/04
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 60/519,143 2003-11-12 U.S.A.
2 10/883,077 2004-07-01 U.S.A.