Source: http://www.google.com/patents/US6624596?dq=5463388
Timestamp: 2014-03-10 17:32:11
Document Index: 159693115

Matched Legal Cases: ['art 24', 'art 23', 'art 24', 'art 23', 'art 24', 'art 23', 'art 23', 'art 24', 'art 23', 'art 24', 'art 23', 'art 24', 'art 23', 'art 23', 'art 23', 'art 24', 'art 23', 'art 24', 'art 23', 'art 24', 'art 24', 'art 23', 'art 24', 'art 23', 'art 24', 'art 24', 'art 24', 'art 23', 'art 24']

Patent US6624596 - Device for lighting discharge lamp - Google PatentsSearch Images Maps Play YouTube News Gmail Drive More »Sign inAdvanced Patent SearchPatentsThe discharge lamp lighting device according to the present invention is provided with a high-voltage generating transformer which comprises a core, a secondary winding part disposed in a plurality of sections on the outside of the core, and a primary winding part disposed on the outside of the secondary...http://www.google.com/patents/US6624596?utm_source=gb-gplus-sharePatent US6624596 - Device for lighting discharge lampAdvanced Patent SearchPublication numberUS6624596 B1Publication typeGrantApplication numberUS 10/110,432PCT numberPCT/JP2000/005516Publication dateSep 23, 2003Filing dateAug 17, 2000Priority dateAug 17, 2000Fee statusPaidAlso published asDE00953472T1, DE60027610D1, DE60027610T2, EP1311143A1, EP1311143A4, EP1311143B1, WO2002015647A1Publication number10110432, 110432, PCT/2000/5516, PCT/JP/0/005516, PCT/JP/0/05516, PCT/JP/2000/005516, PCT/JP/2000/05516, PCT/JP0/005516, PCT/JP0/05516, PCT/JP0005516, PCT/JP005516, PCT/JP2000/005516, PCT/JP2000/05516, PCT/JP2000005516, PCT/JP200005516, US 6624596 B1, US 6624596B1, US-B1-6624596, US6624596 B1, US6624596B1InventorsTakasi Ohsawa, Yoshihisa KawasakiOriginal AssigneeMitsubishi Denki Kabushiki KaishaExport CitationBiBTeX, EndNote, RefManPatent Citations (4), Referenced by (10), Classifications (10), Legal Events (3) External Links: USPTO, USPTO Assignment, EspacenetDevice for lighting discharge lampUS 6624596 B1Abstract The discharge lamp lighting device according to the present invention is provided with a high-voltage generating transformer which comprises a core, a secondary winding part disposed in a plurality of sections on the outside of the core, and a primary winding part disposed on the outside of the secondary winding part and in which a high-voltage side terminal of said secondary winding part is connected to a terminal of the core and a low-voltage side terminal of the secondary winding part is connected to a terminal of the primary winding part.
TECHNICAL FIELD The present invention relates to a discharge lamp lighting device for lighting a discharge lamp that is used as a headlight of an automobile or similar vehicle.
BACKGROUND ART Among discharge lamps, such high intensity discharge lamps (HIDs) as a metal halide lamp, high pressure sodium lamp, mercury vapor lamp have been used as lights for outdoor and indoor facilities, warehouses, factories etc., and as streetlights, and so forth since they have the advantages of large luminous flux, high lamp efficiency and longevity. In recent years, they have come into use, in particular, as headlights of automobiles and the like. To light discharge lamps of this kind, a high starting voltage needs to be applied on startup�this necessitates the use of a lighting device provided with an igniter for generating the starting voltage as well as a stabilizer for stable lighting of the discharge lamp.
DISCLOSURE OF THE INVENTION A discharge lamp lighting device according to an aspect of the present invention is characterized by the provision of a high-voltage generating transformer comprising a core, a secondary winding part disposed in a plurality of sections on the outside of said core, and a primary winding part disposed outside said secondary winding part, wherein a high-voltage side terminal of said secondary winding part is connected to a terminal of said core and a low-voltage side terminal of said secondary winding part is connected to a terminal of said primary winding part. With this construction, it is possible to reduce the insulation capacity in the high-voltage generating transformer and decrease the number of parts such as insulating members, achieving miniaturization of the transformer. Further, since the secondary winding part disposed on the core is divided into a plurality of sections, it is possible to suppress the potential difference between the beginning and end of the winding in each section and increase the withstand voltage of the entire secondary winding part 24 by increasing the number of winding grooves. Furthermore, since the primary winding part is disposed in the same space as that of the secondary winding divided by the respective sections of the winding grooves, it is possible to increase the power transfer efficiency from the primary winding part to the secondary winding part and hence improve the transformer coupling property. Additionally, since the primary winding part is disposed on the secondary winding part over plural sections, it is possible to cause the magnetic flux emanating from the primary winding part to cross the secondary winding part 23 over a wide range, thereby permitting generation of a high voltage from the secondary winding part through electro-magnetic induction.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view showing the internal construction of a high voltage generating transformer for use as an igniter in a conventional lighting device.
FIG. 6 is a sectional view taken along the line VI�VI in FIG. 5.
BEST MODE FOR CARRYING OUT THE INVENTION A detailed description will be given, with reference to the accompanying drawings, of the best mode for carrying out the present invention.
Embodiment 1 FIG. 2 is a front view of a bobbin having a plurality of sections that is used in a high voltage generating transformer for a discharge lamp lighting device according to Embodiment 1 of the present invention; FIG. 3 is a front view of the bobbin of FIG. 2 with a secondary winding wound around it in sections; FIG. 4(a) is a plan view for explaining a method for retaining the secondary winding wound in the respective sections depicted in FIG. 2; FIG. 4(b) is a plan view showing on an enlarged scale a winding retaining part depicted in FIG. 4(a); FIG. 5 is a front view of the bobbin with a primary winding wound on the secondary winding depicted in FIG. 3; FIG. 6 is a sectional view taken along the line VI�VI in FIG. 5; FIG. 7 is a perspective view schematically showing the internal construction of a high withstand-voltage wire for use as a primary winding of the high-voltage generating transformer shown in FIG. 2; and FIG. 8 is a schematic diagram for explaining the withstand voltage of the entire secondary winding wound around the bobbin for use in the high-voltage generating transformer depicted in FIGS. 5 and 6 and the withstand voltage of the secondary winding for each section.
The primary winding part 24 is provided by winding a wire around the Bobbin in the winding grooves 14 to 16 except the winding groove 17 that is the highest voltage side of the secondary winding part 23. The primary winding part 24 is disposed in winding grooves 14 to 16 on the low-voltage side of the secondary winding part 23, but since it lies directly on the secondary winding part 23, a high-withstand-voltage wire is used as the wire forming the primary winding part 24. The high-withstand-voltage wire 25 is of the type that a conductor 26 as of copper is covered with a first insulating layer 27 to provide dielectric strength as depicted in FIG. 7. The first insulating layer 27 may preferably be formed of heat-resistant polytetrafluoroethylene in view of the fact that the primary winding is exposed to high temperatures as well as, high voltages. The polytetrafluoroethylene is a resin of the fluorine series by du Pont that is presently available in the marketplace under the trade name �Teflon.� The high-withstand-voltage wire 25 is wound directly around the secondary winding part 23 and then it is sealed using an epoxy resin to prevent leakage of the high voltage generated by the transformer, but since adhesion between the sealing resin and the above-mentioned fluorine-series resin is poor, the first insulating layer needs to be covered with a second insulating layer 28 to provide appropriate adhesion as shown in FIG. 7. The second insulating layer 28 may preferably be formed using a polyester film that possesses the property of ensuring the adhesion between the two resins. Since the polyester film has the property of being incapable of extrusion, it cannot be coated directly around the first insulating layer 27. For this reason, a polyester film in tape form, for instance, is wrapped helically around the first insulating layer 27 to form the second insulating layer 28 of a predetermined thickness.
In Embodiment 1, the primary winding part 24 is disposed in the winding grooves 14, 15 and 16 on the lower voltage side of the secondary winding part 23 as described above for the reasons given below. If the primary winding part 24 is disposed in the winding groove 17 on the highest voltage side of the secondary winding part 23 as well, the primary winding part 23 is disposed substantially uniformly all over the secondary winding part 23�this enables the magnetic flux from the primary winding part 24 to cross the entire structure of the secondary winding part 23, providing increased efficiency of power transfer from the primary winding part 24 to the secondary winding part 23 and hence increasing the transformer coupling characteristic. On the other hand, when the primary winding part 24 is disposed also in the winding groove 17 that is a section for generating the highest voltage, the insulation on a wire of a dielectric strength against high dielectric breakdown becomes thick, resulting in the inconvenience of making the product bulky. Accordingly, by mounting the primary winding part 24 in the winding grooves 14, 15 and 16 on the lower voltage side of the secondary winding part 23 as described above, it is possible to attain minimization of the product while maintaining the transformer coupling characteristic.
Incidentally, lighting of the discharge lamp 32 requires heating of electrodes of the discharge lamp and its interelectrode materials after the above-mentioned dielectric breakdown between the electrodes. Even if the dielectric breakdown is produced by the high-voltage pulse of the voltage increase rate lowered by the above-mentioned inductance component, the current subsequent to the breakdown is limited by the inductance component, and hence it does not sufficiently heat the electrodes and the interelectrode materials�this readily brings about a situation in which the heat falls short of lighting the discharge lamp and disappears although the breakdown is already produced.
T={square root over (1−Lshort)/Lopen)}, where Lshort is an inductance when the switch 30 is open and Lopen is an inductance when the switch 30 is closed.
In Embodiment 1, since the primary winding part 24 is disposed in the winding grooves 14, 15 and 16 on the low-voltage side of the secondary winding part 23, the primary winding part 24 needs not to have an excessive dielectric strength that the insulation of the primary winding part 24 would be required to possess when the primary winding part 24 is disposed also in the section on the high-voltage side of the secondary winding part 23�this allows a margin for the withstand voltage and avoids the necessity for providing a thick insulation in the primary winding part 24 and hence permits miniaturization of the high-voltage generating transformer accordingly.
INDUSTRIAL APPLICABILITY As described above, the discharge lamp lighting device according to the present invention is suitable for lighting a discharge lamp that is used as a headlight of an automobile or similar vehicle.
Patent CitationsCited PatentFiling datePublication dateApplicantTitleUS6191675 *Apr 20, 1999Feb 20, 2001Hitachi, Ltd.High voltage transformer and ignition transformer using the sameJP2001257088A * Title not availableJPH0851035A Title not availableJPS62293705A Title not available* Cited by examinerReferenced byCiting PatentFiling datePublication dateApplicantTitleUS7142082 *Sep 14, 2001Nov 28, 2006Matsushita Electric Works, Ltd.Electromagnetic device and high-voltage generating device and method of producing electromagnetic deviceUS7394340Oct 11, 2006Jul 1, 2008Matsushita Electric Works, Ltd.Electromagnetic device, high-voltage generating device, and method for making the electromagnetic deviceUS7652550 *Nov 21, 2006Jan 26, 2010Mitsubishi Electric CorporationHigh-voltage generating transformer for discharge lamp lighting apparatusUS7667564 *Oct 18, 2005Feb 23, 2010Delphi Technologies, Inc.Multicharge ignition coil with primary routed in shield slotUS7696702 *Dec 4, 2007Apr 13, 2010Sony CorporationTransformer, backlight apparatus, and display apparatusUS7760061Aug 31, 2006Jul 20, 2010General Electric CompanyLamp transformerUS7855625Dec 27, 2006Dec 21, 2010General Electric CompanyLamp transformerUS8193891Feb 13, 2009Jun 5, 2012Koninklijke Philips Electronics N.V.High voltage transformer with space-saving primary windingsUS8436711 *Nov 18, 2009May 7, 2013Osram Gesellschaft Mit Beschrankter HaftungIntegrated gas discharge lamp and ignition transformer for an integrated gas discharge lampUS20110234356 *Nov 18, 2009Sep 29, 2011Roehl ManfredIntegrated Gas Discharge Lamp and Ignition Transformer for an Integrated Gas Discharge Lamp* Cited by examinerClassifications U.S. Classification315/276, 336/220, 315/289, 336/195, 336/221, 336/212, 315/78International ClassificationH05B41/04Cooperative ClassificationH05B41/042European ClassificationH05B41/04BLegal EventsDateCodeEventDescriptionFeb 24, 2011FPAYFee paymentYear of fee payment: 8Feb 26, 2007FPAYFee paymentYear of fee payment: 4Apr 12, 2002ASAssignmentOwner name: MITSUBISHI DENKI KABUSHIKI KAISHA, JAPANFree format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:OHSAWA, TAKASI;KAWASAKI, YOSHIHISA;REEL/FRAME:013039/0069Effective date: 20020314Owner name: MITSUBISHI DENKI KABUSHIKI KAISHA 2-3, MARUNOUCHIFree format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:OHSAWA, TAKASI /AR;REEL/FRAME:013039/0069RotateOriginal ImageGoogle Home - Sitemap - USPTO Bulk Downloads - Privacy Policy - Terms of Service - About Google Patents - Send FeedbackData provided by IFI CLAIMS Patent Services©2012 Google