Title of Invention	"ELECTRIC LAMP CAPPED WITHOUT CEMENT"
Abstract	Electric lamp capped without cement, the lamp having a lamp cap which has a metal holder part (42; 52) in which the bulb (40; 50) of the lamp is fixed, the lamp cap having a metal support sleeve (43; 53), connected to the metal holder part (42, 52), and a plastic cap part (44; 54) which is provided with the electrical connections (45; 55) of the lamp and in which the metal support sleeve (43; 53) is anchored, the lamp cap having a plurality of reference lugs (43b; 53a), lying in a plane, characterized in that the reference lugs (43b; 53a) are made of a metal and are formed integrally with the metal support sleeve (43; 53).

Title of Invention

"ELECTRIC LAMP CAPPED WITHOUT CEMENT"

Abstract

Electric lamp capped without cement, the lamp having a lamp cap which has a metal holder part (42; 52) in which the bulb (40; 50) of the lamp is fixed, the lamp cap having a metal support sleeve (43; 53), connected to the metal holder part (42, 52), and a plastic cap part (44; 54) which is provided with the electrical connections (45; 55) of the lamp and in which the metal support sleeve (43; 53) is anchored, the lamp cap having a plurality of reference lugs (43b; 53a), lying in a plane, characterized in that the reference lugs (43b; 53a) are made of a metal and are formed integrally with the metal support sleeve (43; 53).

Full Text	The present invention relates to an electric lamp capped without cement. The invention relates to an electric lamp capped without cement according to the preamble of Patent Claim 1 or 4 and to an electric lamp, capped without cement, and a reflector according to the preamble of Claim 16 or 17. Such an' electric lamp capped without cement is, for example, disclosed in American Patent US 4 412 273. The lamp described therein is a single-cap incandescent halogen lamp for use in a motor-vehicle headlight. This lamp consists of a lamp cap made of metal and plastic parts. The lamp cap has a cup-like metal fastening ring, a metal support sleeve and a plastic cap base which is provided with the electrical connections of the lamp. The support sleeve protrudes telescopically out of the cap base in which it is anchored, and is welded to the fastening ring using a plurality of integrally formed welding tabs. The fastening ring has a recess in which the end of the pinch of the lamp bulb is fixed. The plastic cap base has an annular flange and an alignment plate. Between the flange and the alignment plate, there is an annularly extending groove for receiving a gasket which seals off the reflector opening designed as a lamp socket. The alignment plate approximately ends at the inner side of the reflector. A disadvantage is that the alignment plate, in this case made of plastic, of the cap base is directly exposed to the infrared radiation emitted by the lamp, because the plastic tends to give off vapours when heated, and this fogs the reflector. Furthermore, the plastic has a comparatively high coefficient of thermal expansion, so that heating the alignment plate by irradiation with the infrared radiation generated by the lamp causes misalignment of the light source. In addition, the telescopic design of the support sleeve has the disadvantage that the lamp has a comparatively large overall length and requires correspondingly deep reflectors. The object of the invention is to provide an electric lamp, capped without cement and for installation in a reflector, having an improved lamp cap. This object is achieved according to the invention by means of the characterizing features of Patent Claim 1, 4, 16 or 17. Particularly advantageous embodiments of the invention are described in the subclaims. The electric lamp, capped without cement, is intended for installation in a reflector, for example the reflector of a motor-vehicle headlight. The lamp has a lamp cap made of metal and plastic parts. The lamp cap has a metal holder part in which the lamp bulb is fixed, a metal support sleeve supporting the holder part and a plastic cap part which is provided with the electrical connections of the lamp and in which the support sleeve is anchored. The plastic cap part has a plurality of reference lugs, located. in a common plane, which on the one hand are used for holding the lamp in the reflector, and on the other hand determine the position of the light source in the reflector and define the reference plane for aligning the light source when the lamp cap is being fitted. These plastic reference lugs engage in the reflector opening, which is designed as a lamp socket, and according to the invention are each covered by a cover clip, integrally formed on the metal support sleeve, so that the reference lugs are screened against the electromagnetic radiation generated by the lamp, in particular against infrared radiation. For this purpose the cover clips advantageously cover the upper sides of the reference lugs facing the lamp bulb. The cover clips prevent, on the one hand, the plastic reference lugs from giving off vapours and fogging the reflector and, on the other hand, the light source from migrating from its originally exactly adjusted position as a result of the thermal expansion of the reference lugs. The metal cover clips have a much lower thermal expansion as well as higher stiffness than the plastic reference lugs, and prevent thermally induced deformation of the reference lugs and the concomitant misalignment of the light source in the reflector. At the reference lugs, they give the lamp cap greater mechanical stability, in particular when heated. In another embodiment of the invention, the object of the invention is achieved in that the reference lugs which engage in the reflector opening designed as a lamp socket are made of metal and are formed integrally with the metal support sleeve. By virtue of these measures, the lamp cap is given greater mechanical stability, and misalignment of the light source in the reflector, due to the thermal expansion of the lamp cap, is furthermore prevented. The support sleeve is advantageously made of steel or German silver. Both thermoplastics and thermosetting plastics are appropriate for the plastic cap part. Advantageously, the metal support sleeve of the lamp according to the invention is annularly designed and is matched to the engagement diameter of the reflector opening designed as a lamp socket, and is also provided with at least one pressure spring which bears on the reflector wall after the lamp has been installed in the reflector at the lamp socket. This at least one pressure spring ensures that the lamp is seated firmly in the lamp socket of the reflector and compensates for slight tolerances in the manufacture of the lamp cap and of the reflector opening designed as a lamp socket. The at least one pressure spring is advantageously designed as a bent leaf spring. According to a preferred illustrative embodiment of the invention, one end of the leaf spring is welded to the metal support sleeve, while the other bears on the lamp cap such that it can slide, so that the leaf spring bears resiliently on on [sic] the edge of the reflector opening designed as a lamp socket after the lamp has been installed. In another preferred illustrative embodiment, the ends of the leaf spring are each arranged in a hollow recess between the metal support sleeve and the plastic cap part, so that the leaf spring bears resiliently on the edge of the reflector opening designed as a lamp socket after the lamp has been installed. The pressure spring is advantageously made of a spring steel. The plastic cap part is generally produced using an injection-moulding process. The metal support sleeve is advantageously either injected into the plastic cap part or anchored in the plastic cap part by catch or snap fastenings. The holder part is advantageously connected to the support sleeve via an intermediate ring which is provided with integrally formed, angled-off welding clips. The welding clips of the intermediate ring are then advantageously welded to the cover clips integrally formed on the support sleeve or to the metal reference lugs. The intermediate ring provides two additional degrees of freedom for the alignment of the light source, so that five-axis alignment of the light source is made possible. The plastic cap part has an annularly extending, preferably conically designed groove for receiving a gasket. The internal diameter of the gasket is advantageously accurately matched to the circular, conically designed groove and varies linearly with the height of the gasket. These measures ensure that the gasket is seated without play on the plastic cap part and cannot fall off the cap. The lamp cap of the electric lamp according to the invention combines the advantages of a metal cap, that is to say low manufacturing tolerances and the possibility of exact alignment for the light source, with the advantages of a plastic cap, that is to say inexpensive manufacture and simple sealing of the cap. The present invention relates an electric lamp capped without cement the lamp having a lamp cap which has a metal holder part in which the bulb of the lamp is fixed, the lamp cap having a metal support sleeve, connected to the metal holder part, and a plastic cap part which is provided with the electrical connections of the lamp and in which the metal support sleeve is anchored, the lamp cap having a plurality of reference lugs, lying in a plane, characterized in that the reference lugs are made of a metal and are formed integrally with the metal support sleeve. The invention will be explained in more detail below with the aid of several illustrative embodiments. Figure 1 shows a schematized side view of an electric lamp, capped without cement, according to the first illustrative embodiment of the invention, in partially sectional representation Figure 2 shows a plan view of the lamp according to the first illustrative embodiment of the invention Figure 3 shows a schematized side view of an electric lamp, capped without cement, according to the second illustrative embodiment of the invention, in partially sectional representation Figure 4 shows a plan view of the lamp according to the second illustrative embodiment of the invention Figure 5 shows a schematized side view of an electric lamp, capped without cement, according to the third illustrative embodiment of the invention, in partially sectional representation Figure 6 shows a schematized side view of an electric lamp, capped without cement, according to the fourth illustrative embodiment of the invention, in partially sectional representation Figure 7 shows a first embodiment for a pressure spring of the lamp according to the invention Figure 8 shows a second embodiment for a pressure spring of the lamp according to the invention Figure 9 shows a schematized side view of an electric lamp, capped without cement, according to the fifth illustrative embodiment of the invention, in partially sectional representation Figure 10 shows a plan view of the plastic cap part into which the support sleeve is injected according to the fifth illustrative embodiment Figure 11 shows a side view of the pressure spring according to the fifth illustrative embodiment of the invention. The first illustrative embodiment of the lamp capped without cement according to the invention (Figures 1 and 2) is a single-filament incandescent halogen lamp which is intended for use in a motor-vehicle headlight. This lamp has an essentially cylindrical glass lamp bulb 10 with a pinch-sealed lamp bulb end 10a which is generally referred to as the pinch end 10a. The dome 10b of the lamp bulb 10 is provided with a black, light-absorbing coating. The light source used is an incandescent filament 10c, aligned parallel to the axis of the " lamp bulb and electrically connected to electrical supply leads 11 led out from the pinch end 10a. The lamp bulb 10 is fixed via its pinch end 10a in a metal holder part 12 designed as a fastening ring. The fastening ring 12 is supported by an annular metal support sleeve 13. The support sleeve 13 has four integrally formed welding tabs 13a which are spot-welded or laser-welded to the fastening ring 12. In addition to the metal fastening ring 12 and the metal support sleeve 13, the lamp cap also has a plastic cap part 14 which is provided with the electrical connections 15 of the lamp and in which the support sleeve 13 is anchored. The electrical connections 15 of the lamp are each welded to one of the electrical supply leads 11. The plastic cap part 14 is an injection-moulded part into which the metal support sleeve 13 is injected. The plastic cap part 14 has three integrally formed reference lugs 14a, arranged equidistantly along a circumference, which are used for aligning the incandescent filament 10c and for fastening the lamp in the reflector 17 of the headlight. The reference lugs 14a, engaging in the opening 17a in the reflector 17 which is designed as a lamp socket, are each covered by a cover clip 13b integrally formed on the support sleeve 13 and angled-off therefrom, and are thus screened against the infrared radiation generated by the incandescent filament 10c. For this purpose the cover clips 13b cover the upper sides of the reference lugs 14a facing the lamp bulb. The plastic cap part 14 furthermore has an annularly extending, conically designed groove 14b, in which a rubber or silicone gasket 16 is. arranged. The gasket 16 bears on the outside of the reflector wall 17 and seals off the reflector opening 17a designed as a lamp socket. The internal diameter of the gasket 16 is accurately matched to the conically designed groove 14b and varies linearly with the gasket height. The plastic cap part 14 is plugged with a casting compound which seals off the lamp cap at the electrical supply leads 11. The three reference lugs 14a, the gasket 16 and a pressure spring 13c, integrally formed below a reference lug 14a on the metal support sleeve 13, are used for fastening the lamp in the correct position in the lamp socket 17a of the reflector. The lamp cap and the lamp socket 17a form a bayonet connection. In order to install the lamp in the reflector, the lamp is inserted, with the lamp bulb 10 forwards, into the reflector opening 17a designed as a lamp socket, the three reference lugs 14a each engaging through a matched recess in the edge of the opening 17a. The lamp is then rotated in the lamp socket until it reaches a stop (not shown) , so that the reflector wall 17 is clamped between the reference lugs 14a and the gasket 16. The pressure spring 13c bears resiliently on the edge of the reflector opening 17a designed as a lamp socket. In order to prevent erroneous installation of the lamp in the reflector, one of the three reference lugs 14a has a different shape from the other two reference lugs 14a. The same is, of course, also true for. the recesses in the opening 17a designed as a lamp socket which are matched to the reference lugs 14a. Details of the pressure spring 13c are represented in Figures 7 and 8. A second illustrative embodiment of the invention is schematically represented in Figures 3 and 4. This second illustrative embodiment differs from the first illustrative embodiment essentially only by an intermediate ring 28 which is inserted as an additional cap component and connects the fastening ring to the support sleeve. The second illustrative embodiment of the lamp capped without cement according to the invention is likewise a single-filament incandescent halogen lamp which is intended for use in a motor-vehicle headlight. This lamp has an essentially cylindrical glass lamp bulb 20 with a pinch-sealed lamp bulb end 20a which is generally referred to as a pinch end 20a. The dome 20b of the lamp bulb 20 is provided with a black light-absorbing coating. The light source used is an incandescent filament 20c, aligned parallel to the axis of the lamp bulb, which is electrically connected to electrical supply leads 21 led out from the pinch end 20a. The lamp bulb 20 is fixed by its pinch end 20a in a metal holder part 22 designed as a fastening ring. The fastening ring 22 is supported by a metal intermediate ring 28 which is provided with three integrally formed, angled-off welding clips 28a. The three welding clips 28a of the intermediate ring 28 are each laser-welded to a cover clip 23a of an annular metal support sleeve 23. In addition to the metal fastening ring 22, the intermediate ring 28 and the metal support sleeve 23, the lamp cap also has a plastic cap part 24 which is provided with the electrical connections 25 of the lamp and in which the support sleeve 23 is anchored. The electrical connections 25 of the lamp are each welded to one of the electrical supply leads 21. The plastic cap part 24 is an injection-moulded part into which the metal support sleeve 23 is injected. The plastic cap part 24 has three integrally formed reference lugs 24a, arranged equidistantly along a circumference, which are used for aligning the incandescent filament 20c and for fastening the lamp in the reflector 27 of the headlight. The reference lugs 2.4a, which engage in the opening 27a of the reflector 27 which is designed as a lamp socket, are each covered by a cover clip 23a, integrally formed on the support sleeve 23 and angled-off therefrom, and thus screened against the infrared radiation generated by the incandescent filament 20c. The welding clips 28a of the intermediate ring 28 are laser-welded to these cover clips 23a (Figure 4) . The intermediate ring 28 provides additional possibilities for alignment in the reference plane defined by the reference lugs 24a. The plastic cap part 24 furthermore has an annularly extending, conically designed groove 24b in which a rubber or silicone gasket 2 6 is arranged. The gasket 2 6 bears on the outside of the reflector wall 27 and seals off the reflector opening 27a designed as a lamp socket. The internal diameter of the gasket 26 is accurately matched to the conically designed groove 24b and varies linearly with the gasket height. The plastic cap part 24 is plugged with a casting compound which seals off the lamp cap at the electrical supply leads 21. The three reference lugs 24a, the gasket 26 and three pressure springs 23c, integrally formed below the reference lugs 24a on the metal support sleeve 23, are used for fastening the lamp in the lamp socket 27a of the reflector. The lamp cap and the lamp socket 27a form a bayonet connection. In order to install the lamp in the reflector, the lamp is inserted, with the lamp bulb 20 forwards, into the reflector opening 27a designed as a lamp socket, the three reference lugs 24a each engaging through a matched recess in the edge of the opening 27a. The lamp is then rotated in the lamp socket until it meets a stop, so that the reflector wall 27 is clamped between the reference lugs 24a and the gasket 26. The pressure springs 23c bear resiliently on the edge of the reflector opening 27a designed as a lamp socket. In order to prevent erroneous installation of the lamp in the reflector, one of the three reference lugs 24a has a different shape from the other two reference lugs 24a. The same is, of course, also true for the recesses in the opening 27a designed as a lamp socket, which are matched to the reference lugs 24a. Details of the pressure springs 23c are represented in Figures 7 and 8. Figure 5 shows a third illustrative embodiment of the lamp capped without cement according to the invention. Like the lamp in the first illustrative embodiment, this lamp is a single-filament incandescent halogen lamp, equipped with a metal/plastic cap, to be employed in the reflector of a motor-vehicle headlight. This lamp has an essentially cylindrical glass lamp bulb 30 with a pinch-sealed lamp-bulb end 30a which is generally referred to as the pinch end 30a. The dome 30b of the lamp bulb 30 is provided with a black light-absorbing coating. The light source used is an incandescent filament 30c, aligned parallel to the axis of the lamp bulb, which is electrically connected to electrical supply leads 31 led out from the pinch end 30a. The lamp bulb 30 is fixed via its pinch end 30a in a metal holder part 32 designed as a fastening ring. The fastening ring 32 is supported by an annular metal support sleeve 33. The support sleeve 33 has four integrally formed welding tabs 33a, which are spot-welded or laser-welded to the fastening ring 32. In addition to the metal fastening ring 32 and the metal support sleeve 33, the lamp cap also has a plastic cap part 34 which is provided with the electrical connections 35 of the lamp and in which the support sleeve 33 is anchored. The electrical connections 35 of the lamp are each welded to one of the electrical supply leads 31. The plastic cap part 34 is an injection-moulded part, into which the metal support sleeve 33 is fitted. The metal support sleeve 33 is provided with a plurality of claws 33d which dig into the plastic cap part 34 when the support sleeve 33 is fitted, and thus make a permanent connection between the plastic cap part 34 and the support sleeve 33. The metal support sleeve 33 is injected into a moulded part 39 which is made of a plastic which can withstand higher thermal loading than the plastic cap part 34. In contrast to the first two illustrative embodiments, the plastic cap part 34 does not engage in the opening 37a of the reflector 37 which is designed as a lamp socket, but ends on the outside of the reflector wall 37. The plastic moulded part 39 has three integrally formed reference lugs 39a, arranged equidistantly along a circumference, which are used for aligning the -incandescent filament 30c and for fastening the lamp in the reflector of the headlight. The reference lugs 39a, which engage in the opening 37a of the reflector 37 which is designed as a lamp socket, are each covered by a cover clip 33b, integrally formed on the support sleeve 33 and angled-off therefrom, and thus screened against the infrared radiation generated by the incandescent filament 30c. The plastic cap part 34 has an annularly extending, conically designed groove 34b, in which a rubber or silicone gasket 36 is arranged. The gasket 36 bears on the outside of the reflector wall 37 and seals off the reflector opening 37a designed as a lamp socket. The internal diameter of the gasket 36 is accurately matched to the conically designed groove 34b and varies linearly with the gasket height. The plastic cap part 34 is plugged with a casting compound which seals off the lamp cap at the electrical supply leads' 31. The three reference lugs 39a, the gasket 36 and a pressure spring 33c, integrally formed below a reference lug 39a on the metal support sleeve 33, are used for fastening the lamp in the lamp socket 37a of the reflector. The lamp cap and the lamp socket 37a form a bayonet connection. In order to install the lamp in the reflector, the lamp is inserted, with the lamp bulb 30 forwards, into the reflector opening 37a designed as a lamp socket, the three reference lugs 39a each engaging through a matched recess in the edge of the opening 37a. The lamp is then rotated in the lamp socket until it meets a stop, so that the reflector wall 37 is clamped between the reference lugs 39a and the gasket 36. The pressure spring 33c bears resiliently on the edge of the reflector opening 37a designed as a lamp socket. In order to prevent erroneous installation of the lamp in the reflector, one of the three reference lugs 39a has a different shape from the other two reference lugs 39a. The same is, of course, also true for the recesses in the opening 37a designed as a lamp socket, which are matched to the reference lugs 39a. Details of the pressure spring 33c are represented in Figures 7 and 8 Figure 6 shows a fourth illustrative embodiment of the invention, again relating to a single-filament incandescent halogen lamp for installation in the reflector of a motor-vehicle headlight. This lamp has an essentially cylindrical glass lamp bulb 40 with a pinch-sealed lamp-bulb end 40a which is generally referred to as the pinch end 40a. The dome 40b of the lamp bulb 40 is provided with a black light-absorbing coating. The light source used is an incandescent filament 40c, aligned parallel to the axis of the lamp bulb, which is electrically connected to electrical supply leads 41 led out from the pinch end 40a. The lamp bulb 40 is fastened via its pinch end 40a in a metal holder part 42 designed as a fastening ring. The fastening ring 42 is supported by an annular metal support sleeve 43. The support sleeve 43 has four integrally formed welding tabs 43a, which are spot-welded to the fastening ring 42. In addition to the metal fastening ring 42 and the metal support sleeve 43, the lamp cap also has a plastic cap part 44 which is provided with electrical connections 45 of the lamp and in which the support sleeve 43 is anchored. The electrical connections 45 of the lamp are each welded to one of the electrical supply leads 41. The plastic cap part 44 is an injection-moulded part, into which the metal support sleeve 43 is fitted. The support sleeve 43 is equipped with a plurality of integrally formed barbs 43d which irremovably hook into recesses 44a, matched to the barbs 43d inside the plastic cap part 44, when the support sleeve 43 is fitted into the plastic cap part 44. The metal support sleeve 43 furthermore has three integrally formed reference lugs 43b which are angled-off from the support sleeve 43. These reference lugs 43b are arranged equidistantly along a circumference and are used for aligning the incandescent filament 40c and for fastening the lamp in the reflector 47. The plastic cap part 44 has an annularly extending, conically designed groove 44b in which a rubber or silicone gasket 46 is arranged. The gasket 46 bears on the outside of the reflector wall 47 and seals off the reflector opening 47a designed as a lamp socket. The internal diameter of the gasket 4 6 is accurately matched to the conically designed groove 44b and varies linearly with the gasket height. The plastic cap part 44 is plugged with a casting compound which seals off the lamp cap at the electrical supply leads 41. The three reference lugs 43b, the gasket 46 and a pressure spring 43c, integrally formed below a reference lug 43b on the metal support sleeve 43, are used for fastening the lamp in the lamp socket 47a of the reflector. The lamp cap and the lamp socket 47a form a bayonet connection. In order to install the lamp in the reflector, the lamp is inserted, with the lamp bulb 40 forwards, into the reflector opening 47a designed as a lamp socket, the three reference lugs 43b each engaging through a matched recess in the edge of the opening 47a. The lamp is then rotated in the lamp socket until it meets a stop, so that the reflector wall 47 is clamped between the reference lugs 43b and the gasket 46. The pressure spring 43c bears resiliently on the edge of the reflector opening 47a designed as a lamp socket. In order to prevent erroneous installation of the lamp in the reflector, one of the three reference lugs 43b has a different shape from the other two reference lugs 43b. The same is, of course, also true for the recesses in the opening 47a designed as a lamp socket, which are matched to the reference lugs 43b. Details of the pressure spring 43c are represented in Figures 7 and 8. In contrast to the first two illustrative embodiments, the plastic cap part 44, provided with the electrical connections 45 of the lamp, here again, as in the third illustrative embodiment, does not engage into the opening 47a of the reflector 47 designed as a lamp socket. However, unlike in the third illustrative embodiment, in this fourth illustrative embodiment the plastic parts are completely left out at the opening 47a, in order to reduce the risk of the insideof the reflector wall 47 being fogged by the vapours being given off by the plastic lamp parts. In this fourth illustrative embodiment, the plastic reference lugs in illustrative embodiments one to three are replaced by metal reference lugs 43b. Figures 7 and 8 show two different embodiments of the pressure spring 13c, 23c, 33c, 43c fitted on the metal support sleeve. The embodiment of the pressure spring shown in Figure 7 can be applied to all four above-mentioned illustrative embodiments, while the embodiment of the pressure springs represented in Figure 8 can only be used in illustrative embodiments 1 to 3. Figure 7 shows a cross-section through the lamp cap, in a plane perpendicular to the axis of the lamp and extending through the pressure spring. The pressure spring 70 is designed as a bent leaf spring and is provided with plane ends 70a and arranged equidistantly along the outer wall of the annular metal support sleeve 71. On one side, the pressure spring 70 is welded via the plane end 70b onto the outer wall of the support sleeve 71, while the other end 70a of the pressure spring 70 bears loosely on the outer wall of the support sleeve 71, so that the end 70a slides on the outer wall of the support sleeve 71 when pressure is exerted on the outwardly bent region 70c of the pressure spring 70. At the pressure spring 70, the annularly designed support sleeve 71 in each case has a plane, that is to say not bent, region 71a on which the ends 70a, 70b of the pressure spring 70 bear. The support sleeve 71 [lacuna] anchored in the plastic cap part 72. The outwardly bent region 70c of the pressure spring 70 bears on the edge of the reflector opening designed as a lamp socket, after the lamp has been installed in the reflector. Figure 8 shows the second embodiment of the pressure spring, in a section plane through the lamp cap, perpendicular to the axis of the lamp and extending through the pressure spring. Here again, the pressure spring 80 is designed as an outwardly bent leaf spring. The two ends 80a, 80b of the leaf - spring 80 are each inserted into a hollow recess 82a, 82b between the metal support sleeve 81 and the plastic cap part 82. The outwardly bent region 80c of the leaf spring 80 protrudes from the outer wall of the annular support sleeve 81. When pressure is exerted on the bent region of the leaf spring 80, the leaf-spring ends 80a, 80b slide deeper into the hollow recesses 82a, 82b. The outwardly bent region 80c of the pressure spring 80 bears on the edge of the reflector opening designed as a lamp socket, after the lamp has been installed in the reflector. In all illustrative embodiments, the pressure spring consists of a spring steel. Figures 9 to 11 show a fifth illustrative embodiment of the invention. This illustrative embodiment of the lamp capped without cement according to the invention is also a single-filament incandescent halogen lamp, to be employed in a motor-vehicle headlight. This lamp has an essentially cylindrical glass lamp bulb 50 with a pinch-sealed lamp-bulb end 50a which is referred to as the pinch end 50a. The dome 50b of the lamp bulb 50 is provided with a black, light-absorbing coating. The light source used is an incandescent filament 50c, aligned parallel to the axis of the lamp bulb and electrically connected to electrical supply leads 51 led out from the pinch end 50a. The lamp bulb 50 is fixed via its pinch end 50a in a metal holder part 52 designed as a fastening ring. The fastening ring 52 is supported by a metal intermediate ring 58 which in provided with three integrally formed, angled-off welding clips 58a. The intermediate ring 58 in turn is laser-welded to a metal support sleeve 53. In addition to the metal fastening ring 52, the intermediate ring 58, and the metal support sleeve 53, the lamp cap also has a plastic cap part 54 which is provided with the electrical connections 55 of the lamp and in which the support sleeve 53 is anchored. The electrical connections 55 of the lamp are each welded to one of the electrical supply leads 51. The plastic cap part 54 is an injection-moulded part into which the metal support sleeve 53 is injected. The support sleeve 53 has three integrally formed reference lugs 53a, arranged equidistantly along a circumference . which are used for aligning the incandescent filament 50c and for fastening the lamp in the reflector (not shown in Fig. 9) of the headlight. The reference lugs 53a are angled-off from the support sleeve 53 and lie in a common plane. The welding clips 58a of the intermediate ring 58 are laser-welded to the reference lugs 53a. The intermediate ring 58 provides additional possibilities for alignment in the reference plane defined by the reference lugs 53a. The plastic cap part 54 has an annularly extending, conically designed groove 54b, in which a rubber or silicone gasket (not shown in Figure 9) is arranged. The gasket bears on the outside of the reflector wall and seals off the reflector opening designed as a lamp socket. The internal diameter of the gasket in this embodiment is also accurately matched to the conically designed groove 54b and varies linearly with the gasket height. A bent leaf spring 90 (Fig. 11), used to fasten the lamp in the headlight, projects through a passage 53b, located below one of the three reference lugs 53a, in the wall of the annular support sleeve 53. The ends 90a, 90b of the leaf spring 90 bear on the inner wall of the support sleeve 53 and on a stop 59a, 59b, each integrally formed on the plastic cap part 54, so that the leaf spring 90 is clamped between these two stops 59a, 59b formed as holders. The three reference lugs 53a, the gasket arranged in the groove 54b and a pressure spring 90 are used for fastening the lamp in the lamp socket of the reflector. The lamp cap and the lamp socket form a bayonet connection. In order to install the lamp in the reflector, the lamp is inserted, with the lamp bulb 50 forwards, into the reflector opening designed as a lamp socket, the three reference lugs 53a each engaging through a matched recess in the edge of the opening. The lamp is then rotated in the lamp socket until it meets a stop, so that the reflector wall is clamped between the reference lugs 53a and the gasket as described in the fourth illustrative embodiment and shown in Figure 6. The pressure spring 90 bears resiliently on the edge of the reflector opening designed as a lamp socket. In order to prevent erroneous installation of the lamp in the reflector, the three reference lugs 53a all have different shapes. The same is, of course, also true for the recesses in the opening designed as a lamp socket which are matched to the reference lugs 53a. Details of the pressure spring 90 are represented in Figure 11. The pressure spring according to the fifth illustrative embodiment is formed as a bent leaf spring. It has two slightly curved ends 90a, 90b which, after being assembled, bear on the inner wall of the annular support sleeve. The leaf spring 90 is fixed in position moreover by two stops 59a, 59b, integrally formed on the plastic cap part 54, on which the ends 90a, 90b meet. As a result the leaf spring 90 is clamped between the stops 59a, 59b (Figure 10) . The leaf spring has a region 90c bulging outwards in bulbous fashion which projects through the passage 53b in the support sleeve 53 after fitting of the leaf spring 90 and bears on the reflector opening designed as the lamp socket after fitting of the lamp in the headlight. In the plan view of Figure 10 the passage 53b is shown in broken lines only, since it is covered by one of the reference lugs 53a. The outwardly bent region 90c of the leaf spring 90 is connected by two inwardly bent regions 90d and 90e to the respective leaf spring ends 90a and 90b. The reference numeral 60 in Figure 10 denotes the passages for the electrical supply leads 51 of the lamp in the plastic cap part 54. The invention is not restricted to the illustrative embodiments described in detail above. By way of example, the lamp cap according to the invention can also be applied to two-filament incandescent halogen lamps and to high-pressure discharge lamps, which are intended to be used in motor-vehicle headlights. WE CLAIM: 1. Electric lamp capped without cement the lamp having a lamp cap which has a metal holder part (42; 52) in which the bulb (40; 50) of the lamp is fixed, the lamp cap having a metal support sleeve (43; 53), connected to the metal holder part (42, 52), and a plastic cap part (44; 54) which is provided with the electrical connections (45; 55) of the lamp and in which the metal support sleeve (43; 53) is anchored, the lamp cap having a plurality of reference lugs (43b; 53a), lying in a plane, characterized in that the reference lugs (43b; 53a) are made of a metal and are formed integrally with the metal support sleeve (43; 53). 2. Electric lamp capped without cement as claimed in claim 1, wherein the metal support sleeve (13; 23; 33; 43; 71; 81; 53) is designed annularly, the metal support sleeve (13; 23; 33; 43; 71; 81; 53) is provided with at least one pressure spring (13c; 23c; 33c; 43c; 70; 80; 90). 3. Electric lamp capped without cement as claimed in claim 2, wherein the at least one pressure spring (13c; 23c; 33c; 43c; 70; 80; 90) is designed as a bent leaf spring. 4. Electric lamp capped without cement as claimed in claim 2, wherein the at least one pressure spring (13c; 23c; 33c; 43c; 70; 80) is designed as a bent leaf spring, one end (70b) of the pressure spring (70) being welded to the metal support sleeve (71), the other end (70a) bearing on the support sleeve (71) such that it can slide, and the leaf spring (70) bearing resiliently on the edge of the reflector opening (17a; 27a; 37a; 47a) designed as a lamp socket, after the lamp is fitted. 5. Electric lamp capped without cement as claimed in claim 2, wherein the at least one pressure spring (13c; 23c; 33c; 43c; 70; 80) is designed as a bent leaf spring, the ends of the leaf spring (80) each being arranged in a recess (82a, 82b) between the metal support sleeve (81) and the plastic cap part (82), so that the leaf spring (86) bears resiliently on the edge of the reflector opening (17a; 27a; 37a; 47a) designed as a lamp socket, after the lamp is fitted. 6. Electric lamp capped without cement as claimed in claim 1 and 3, wherein the plastic cap part (54) has holders (59a; 59b) between which the ends (90a; 90b) of the at least one leaf spring (90) are clamped, and the support sleeve (53) has a passage (53b) in which the at least one leaf spring (90) engages. 7. Electric lamp capped without cement as claimed in claim 6, wherein: the ends (90a; 90b) of the at least one leaf spring (90) bear on the inner wall of the support sleeve (53), the at least one leaf spring (90) has an outwardly bent region (90c) which engages in the passage (53b), the at least one leaf spring (90) has two inwardly bent regions (90d, 90e) which connect the outwardly bent region (90c) to one of the leaf spring ends (90a, 90b) each. 8. Electric lamp capped without cement as claimed in claim 3, wherein the at least one pressure spring (13c; 23c; 33c; 43c; 70; 80; 90) is made of a spring steel. 9. Electric lamp capped without cement as claimed in claim 1, wherein the support sleeve (13; 23; 33; 43; 71; 81; 53) is made of steel or German silver. 10. Electric lamp capped without cement as claimed in claim 1, wherein the holder part (52) is connected to the metal support sleeve (53) via an intermediate ring (58) which is provided with integrally formed, angled-off welding clips (58a), by welding the welding clips (58a) of the intermediate ring (58) to the reference lugs (53 a) of the metal support sleeve (53). 11. Electric lamp capped without cement as claimed in claim 1, wherein the plastic cap part (14; 24; 34; 44; 54) has an annularly extending conically designed groove (14b; 24b; 34b; 44b; 54b) for receiving a gasket (16; 26; 36; 46). 12. Electric lamp capped without cement as claimed in claim 11, wherein the internal diameter of the gasket (16; 26; 36; 46) is accurately matched to the conically designed groove (14b; 24b; 34b; 44b; 54b) and varies linearly with the height of the gasket. 13. Electric lamp capped without cement and reflector, the reflector being provided with an opening (47a) designed as a lamp socket and made in the reflector wall (47), the lamp having a lamp cap which has a metal holder part (42; 52) in which the bulb (40; 50) of the lamp is fixed, the lamp cap having a metal support sleeve (43, 53) connected to the metal holder part (42; 52) and a plastic cap part (44; 54) which is provided with the electrical connections (45; 55) of the lamp and in which the metal support sleeve (43; 53) is anchored, the lamp cap having a plurality of reference lugs (43b; 53a), lying in a plane, which are used for holding and for correct installation of the lamp in the reflector, wherein the reference lugs (43 b, 53 a) are made of a metal and are formed integrally with the metal support sleeve (43; 53), the reference lugs (43b; 53a) engaging into the reflector opening (47a) designed as a lamp socket. 14. Electric lamp capped without cement and reflector as claimed in claim 13, wherein the metal support sleeve (13; 23; 33; 43; 71; 81; 53) is designed annularly, the diameter of the metal support sleeve (13; 23; 33; 43; 71; 81; 53) is matched to the engagement diameter of the reflector opening (17a; 27a; 37a; 47a) designed as a lamp socket, the metal support sleeve (13; 23; 33; 43; 71; 81; 53) is provided with at least one pressure spring (13c; 23c; 33c; 43c; 70; 80; 90) which bears on the reflector wall (17, 27; 37; 47) after the lamp has been fitted in the reflector at the opening (17a; 27a; 37a; 47a) designed as a lamp socket. 15. Electric lamp capped without cement substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

Full Text

The present invention relates to an electric lamp capped without cement.
The invention relates to an electric lamp capped without cement according to the preamble of Patent Claim 1 or 4 and to an electric lamp, capped without cement, and a reflector according to the preamble of Claim 16 or 17.
Such an' electric lamp capped without cement is, for example, disclosed in American Patent US 4 412 273. The lamp described therein is a single-cap incandescent halogen lamp for use in a motor-vehicle headlight. This lamp consists of a lamp cap made of metal and plastic parts. The lamp cap has a cup-like metal fastening ring, a metal support sleeve and a plastic cap base which is provided with the electrical connections of the lamp. The support sleeve protrudes telescopically out of the cap base in which it is anchored, and is welded to the fastening ring using a plurality of integrally formed welding tabs. The fastening ring has a recess in which the end of the pinch of the lamp bulb is fixed. The plastic cap base has an annular flange and an alignment plate. Between the flange and the alignment plate, there is an annularly extending groove for receiving a gasket which seals off the reflector opening designed as a lamp socket. The alignment plate approximately ends at the inner side of the reflector.
A disadvantage is that the alignment plate, in this case made of plastic, of the cap base is directly exposed to the infrared radiation emitted by the lamp, because the plastic tends to give off vapours when heated, and this fogs the reflector. Furthermore, the plastic has a comparatively high coefficient of thermal expansion, so that heating the alignment plate by irradiation with the infrared radiation generated by the lamp causes misalignment of the light source. In addition, the telescopic design of the support sleeve has the

disadvantage that the lamp has a comparatively large overall length and requires correspondingly deep reflectors.
The object of the invention is to provide an electric lamp, capped without cement and for installation in a reflector, having an improved lamp cap.
This object is achieved according to the invention by means of the characterizing features of Patent Claim 1, 4, 16 or 17. Particularly advantageous embodiments of the invention are described in the subclaims.
The electric lamp, capped without cement, is intended for installation in a reflector, for example the reflector of a motor-vehicle headlight. The lamp has a lamp cap made of metal and plastic parts. The lamp cap has a metal holder part in which the lamp bulb is fixed, a metal support sleeve supporting the holder part and a plastic cap part which is provided with the electrical connections of the lamp and in which the support sleeve is anchored.
The plastic cap part has a plurality of reference lugs, located. in a common plane, which on the one hand are used for holding the lamp in the reflector, and on the other hand determine the position of the light source in the reflector and define the reference plane for aligning the light source when the lamp cap is being fitted. These plastic reference lugs engage in the reflector opening, which is designed as a lamp socket, and according to the invention are each covered by a cover clip, integrally formed on the metal support sleeve, so that the reference lugs are screened against the electromagnetic radiation generated by the lamp, in particular against infrared radiation. For this purpose the cover clips advantageously cover the upper sides of the reference lugs facing the lamp bulb. The cover clips prevent, on the one hand, the plastic reference lugs from giving off vapours and fogging the reflector and, on the other hand, the light source from migrating from its originally exactly adjusted position as a result of the
thermal expansion of the reference lugs. The metal cover clips have a much lower thermal expansion as well as higher stiffness than the plastic reference lugs, and prevent thermally induced deformation of the reference lugs and the concomitant misalignment of the light source in the reflector. At the reference lugs, they give the lamp cap greater mechanical stability, in particular when heated.
In another embodiment of the invention, the object of the invention is achieved in that the reference lugs which engage in the reflector opening designed as a lamp socket are made of metal and are formed integrally with the metal support sleeve. By virtue of these measures, the lamp cap is given greater mechanical stability, and misalignment of the light source in the reflector, due to the thermal expansion of the lamp cap, is furthermore prevented.
The support sleeve is advantageously made of steel or German silver. Both thermoplastics and thermosetting plastics are appropriate for the plastic cap part.
Advantageously, the metal support sleeve of the lamp according to the invention is annularly designed and is matched to the engagement diameter of the reflector opening designed as a lamp socket, and is also provided with at least one pressure spring which bears on the reflector wall after the lamp has been installed in the reflector at the lamp socket. This at least one pressure spring ensures that the lamp is seated firmly in the lamp socket of the reflector and compensates for slight tolerances in the manufacture of the lamp cap and of the reflector opening designed as a lamp socket. The at least one pressure spring is advantageously designed as a bent leaf spring. According to a preferred illustrative embodiment of the invention, one end of the leaf spring is welded to the metal support sleeve, while the other bears on the lamp cap such that it can slide, so that the leaf spring bears resiliently on on [sic] the edge of the
reflector opening designed as a lamp socket after the lamp has been installed. In another preferred illustrative embodiment, the ends of the leaf spring are each arranged in a hollow recess between the metal support sleeve and the plastic cap part, so that the leaf spring bears resiliently on the edge of the reflector opening designed as a lamp socket after the lamp has been installed. The pressure spring is advantageously made of a spring steel.
The plastic cap part is generally produced using an injection-moulding process. The metal support sleeve is advantageously either injected into the plastic cap part or anchored in the plastic cap part by catch or snap fastenings.
The holder part is advantageously connected to the support sleeve via an intermediate ring which is provided with integrally formed, angled-off welding clips. The welding clips of the intermediate ring are then advantageously welded to the cover clips integrally formed on the support sleeve or to the metal reference lugs. The intermediate ring provides two additional degrees of freedom for the alignment of the light source, so that five-axis alignment of the light source is made possible. The plastic cap part has an annularly extending, preferably conically designed groove for receiving a gasket. The internal diameter of the gasket is advantageously accurately matched to the circular, conically designed groove and varies linearly with the height of the gasket. These measures ensure that the gasket is seated without play on the plastic cap part and cannot fall off the cap. The lamp cap of the electric lamp according to the invention combines the advantages of a metal cap, that is to say low manufacturing tolerances and the possibility of exact alignment for the light source, with the advantages of a plastic cap, that is to say inexpensive manufacture and simple sealing of the cap.
The present invention relates an electric lamp capped without cement the lamp having a lamp cap which has a metal holder part in which the bulb of the lamp is fixed, the lamp cap having a metal support sleeve, connected to the metal holder part, and a plastic cap part which is provided with the electrical connections of the lamp and in which the metal support sleeve is anchored, the lamp cap having a plurality of reference lugs, lying in a plane, characterized in that the reference lugs are made of a metal and are formed integrally with the metal support sleeve.

The invention will be explained in more detail below
with the aid of several illustrative embodiments.
Figure 1 shows a schematized side view of an electric lamp, capped without cement, according to the first illustrative embodiment of the invention, in partially sectional representation
Figure 2 shows a plan view of the lamp according to the first illustrative embodiment of the invention
Figure 3 shows a schematized side view of an electric lamp, capped without cement, according to the second illustrative embodiment of the invention, in partially sectional representation
Figure 4 shows a plan view of the lamp according to the second illustrative embodiment of the invention
Figure 5 shows a schematized side view of an electric lamp, capped without cement, according to the third illustrative embodiment of the invention, in partially sectional representation
Figure 6 shows a schematized side view of an electric lamp, capped without cement, according to the fourth illustrative embodiment of the invention, in partially sectional representation
Figure 7 shows a first embodiment for a pressure spring of the lamp according to the invention
Figure 8 shows a second embodiment for a pressure spring of the lamp according to the invention
Figure 9 shows a schematized side view of an electric lamp, capped without cement, according to the fifth illustrative embodiment of the invention, in partially sectional representation
Figure 10 shows a plan view of the plastic cap part into which the support sleeve is injected according to the fifth illustrative embodiment
Figure 11 shows a side view of the pressure spring according to the fifth illustrative embodiment of the invention.
The first illustrative embodiment of the lamp capped
without cement according to the invention (Figures 1 and
2) is a single-filament incandescent halogen lamp which is intended for use in a motor-vehicle headlight. This lamp has an essentially cylindrical glass lamp bulb 10 with a pinch-sealed lamp bulb end 10a which is generally referred to as the pinch end 10a. The dome 10b of the lamp bulb 10 is provided with a black, light-absorbing coating. The light source used is an incandescent filament 10c, aligned parallel to the axis of the " lamp bulb and electrically connected to electrical supply leads 11 led out from the pinch end 10a. The lamp bulb 10 is fixed via its pinch end 10a in a metal holder part 12 designed as a fastening ring. The fastening ring 12 is supported by an annular metal support sleeve 13. The support sleeve 13 has four integrally formed welding tabs 13a which are spot-welded or laser-welded to the fastening ring 12. In addition to the metal fastening ring 12 and the metal support sleeve 13, the lamp cap also has a plastic cap part 14 which is provided with the electrical connections 15 of the lamp and in which the support sleeve 13 is anchored. The electrical connections 15 of the lamp are each welded to one of the electrical supply leads 11. The plastic cap part 14 is an injection-moulded part into which the metal support sleeve 13 is injected. The plastic cap part 14 has three integrally formed reference lugs 14a, arranged equidistantly along a circumference, which are used for aligning the incandescent filament 10c and for fastening the lamp in the reflector 17 of the headlight. The reference lugs 14a, engaging in the opening 17a in the reflector 17 which is designed as a lamp socket, are each covered by a cover clip 13b integrally formed on the support sleeve 13 and angled-off therefrom, and are thus screened against the infrared radiation generated by the incandescent filament 10c. For this purpose the cover clips 13b cover the upper sides of the reference lugs 14a facing the lamp bulb. The plastic cap part 14 furthermore has an annularly extending, conically designed groove 14b, in which a rubber or silicone gasket 16 is. arranged. The
gasket 16 bears on the outside of the reflector wall 17 and seals off the reflector opening 17a designed as a lamp socket. The internal diameter of the gasket 16 is accurately matched to the conically designed groove 14b and varies linearly with the gasket height. The plastic cap part 14 is plugged with a casting compound which seals off the lamp cap at the electrical supply leads 11. The three reference lugs 14a, the gasket 16 and a pressure spring 13c, integrally formed below a reference lug 14a on the metal support sleeve 13, are used for fastening the lamp in the correct position in the lamp socket 17a of the reflector. The lamp cap and the lamp socket 17a form a bayonet connection. In order to install the lamp in the reflector, the lamp is inserted, with the lamp bulb 10 forwards, into the reflector opening 17a designed as a lamp socket, the three reference lugs 14a each engaging through a matched recess in the edge of the opening 17a. The lamp is then rotated in the lamp socket until it reaches a stop (not shown) , so that the reflector wall 17 is clamped between the reference lugs 14a and the gasket 16. The pressure spring 13c bears resiliently on the edge of the reflector opening 17a designed as a lamp socket. In order to prevent erroneous installation of the lamp in the reflector, one of the three reference lugs 14a has a different shape from the other two reference lugs 14a. The same is, of course, also true for. the recesses in the opening 17a designed as a lamp socket which are matched to the reference lugs 14a. Details of the pressure spring 13c are represented in Figures 7 and 8.
A second illustrative embodiment of the invention is schematically represented in Figures 3 and 4. This second illustrative embodiment differs from the first illustrative embodiment essentially only by an intermediate ring 28 which is inserted as an additional cap component and connects the fastening ring to the support sleeve. The second illustrative embodiment of the lamp capped without cement according to the invention is
likewise a single-filament incandescent halogen lamp which is intended for use in a motor-vehicle headlight. This lamp has an essentially cylindrical glass lamp bulb 20 with a pinch-sealed lamp bulb end 20a which is generally referred to as a pinch end 20a. The dome 20b of the lamp bulb 20 is provided with a black light-absorbing coating. The light source used is an incandescent filament 20c, aligned parallel to the axis of the lamp bulb, which is electrically connected to electrical supply leads 21 led out from the pinch end 20a. The lamp bulb 20 is fixed by its pinch end 20a in a metal holder part 22 designed as a fastening ring. The fastening ring 22 is supported by a metal intermediate ring 28 which is provided with three integrally formed, angled-off welding clips 28a. The three welding clips 28a of the intermediate ring 28 are each laser-welded to a cover clip 23a of an annular metal support sleeve 23. In addition to the metal fastening ring 22, the intermediate ring 28 and the metal support sleeve 23, the lamp cap also has a plastic cap part 24 which is provided with the electrical connections 25 of the lamp and in which the support sleeve 23 is anchored. The electrical connections 25 of the lamp are each welded to one of the electrical supply leads 21. The plastic cap part 24 is an injection-moulded part into which the metal support sleeve 23 is injected. The plastic cap part 24 has three integrally formed reference lugs 24a, arranged equidistantly along a circumference, which are used for aligning the incandescent filament 20c and for fastening the lamp in the reflector 27 of the headlight. The reference lugs 2.4a, which engage in the opening 27a of the reflector 27 which is designed as a lamp socket, are each covered by a cover clip 23a, integrally formed on the support sleeve 23 and angled-off therefrom, and thus screened against the infrared radiation generated by the incandescent filament 20c. The welding clips 28a of the intermediate ring 28 are laser-welded to these cover clips 23a (Figure 4) . The intermediate ring 28 provides additional possibilities for
alignment in the reference plane defined by the reference lugs 24a. The plastic cap part 24 furthermore has an annularly extending, conically designed groove 24b in which a rubber or silicone gasket 2 6 is arranged. The gasket 2 6 bears on the outside of the reflector wall 27 and seals off the reflector opening 27a designed as a lamp socket. The internal diameter of the gasket 26 is accurately matched to the conically designed groove 24b and varies linearly with the gasket height. The plastic cap part 24 is plugged with a casting compound which seals off the lamp cap at the electrical supply leads 21. The three reference lugs 24a, the gasket 26 and three pressure springs 23c, integrally formed below the reference lugs 24a on the metal support sleeve 23, are used for fastening the lamp in the lamp socket 27a of the reflector. The lamp cap and the lamp socket 27a form a bayonet connection. In order to install the lamp in the reflector, the lamp is inserted, with the lamp bulb 20 forwards, into the reflector opening 27a designed as a lamp socket, the three reference lugs 24a each engaging through a matched recess in the edge of the opening 27a. The lamp is then rotated in the lamp socket until it meets a stop, so that the reflector wall 27 is clamped between the reference lugs 24a and the gasket 26. The pressure springs 23c bear resiliently on the edge of the reflector opening 27a designed as a lamp socket. In order to prevent erroneous installation of the lamp in the reflector, one of the three reference lugs 24a has a different shape from the other two reference lugs 24a. The same is, of course, also true for the recesses in the opening 27a designed as a lamp socket, which are matched to the reference lugs 24a. Details of the pressure springs 23c are represented in Figures 7 and 8.
Figure 5 shows a third illustrative embodiment of the lamp capped without cement according to the invention. Like the lamp in the first illustrative embodiment, this lamp is a single-filament incandescent halogen lamp, equipped with a metal/plastic cap, to be
employed in the reflector of a motor-vehicle headlight. This lamp has an essentially cylindrical glass lamp bulb 30 with a pinch-sealed lamp-bulb end 30a which is generally referred to as the pinch end 30a. The dome 30b of the lamp bulb 30 is provided with a black light-absorbing coating. The light source used is an incandescent filament 30c, aligned parallel to the axis of the lamp bulb, which is electrically connected to electrical supply leads 31 led out from the pinch end 30a. The lamp bulb 30 is fixed via its pinch end 30a in a metal holder part 32 designed as a fastening ring. The fastening ring 32 is supported by an annular metal support sleeve 33. The support sleeve 33 has four integrally formed welding tabs 33a, which are spot-welded or laser-welded to the fastening ring 32. In addition to the metal fastening ring 32 and the metal support sleeve 33, the lamp cap also has a plastic cap part 34 which is provided with the electrical connections 35 of the lamp and in which the support sleeve 33 is anchored. The electrical connections 35 of the lamp are each welded to one of the electrical supply leads 31. The plastic cap part 34 is an injection-moulded part, into which the metal support sleeve 33 is fitted. The metal support sleeve 33 is provided with a plurality of claws 33d which dig into the plastic cap part 34 when the support sleeve 33 is fitted, and thus make a permanent connection between the plastic cap part 34 and the support sleeve 33. The metal support sleeve 33 is injected into a moulded part 39 which is made of a plastic which can withstand higher thermal loading than the plastic cap part 34. In contrast to the first two illustrative embodiments, the plastic cap part 34 does not engage in the opening 37a of the reflector 37 which is designed as a lamp socket, but ends on the outside of the reflector wall 37. The plastic moulded part 39 has three integrally formed reference lugs 39a, arranged equidistantly along a circumference, which are used for aligning the -incandescent filament 30c and for fastening the lamp in
the reflector of the headlight. The reference lugs 39a, which engage in the opening 37a of the reflector 37 which is designed as a lamp socket, are each covered by a cover clip 33b, integrally formed on the support sleeve 33 and angled-off therefrom, and thus screened against the infrared radiation generated by the incandescent filament 30c. The plastic cap part 34 has an annularly extending, conically designed groove 34b, in which a rubber or silicone gasket 36 is arranged. The gasket 36 bears on the outside of the reflector wall 37 and seals off the reflector opening 37a designed as a lamp socket. The internal diameter of the gasket 36 is accurately matched to the conically designed groove 34b and varies linearly with the gasket height. The plastic cap part 34 is plugged with a casting compound which seals off the lamp cap at the electrical supply leads' 31. The three reference lugs 39a, the gasket 36 and a pressure spring 33c, integrally formed below a reference lug 39a on the metal support sleeve 33, are used for fastening the lamp in the lamp socket 37a of the reflector. The lamp cap and the lamp socket 37a form a bayonet connection. In order to install the lamp in the reflector, the lamp is inserted, with the lamp bulb 30 forwards, into the reflector opening 37a designed as a lamp socket, the three reference lugs 39a each engaging through a matched recess in the edge of the opening 37a. The lamp is then rotated in the lamp socket until it meets a stop, so that the reflector wall 37 is clamped between the reference lugs 39a and the gasket 36. The pressure spring 33c bears resiliently on the edge of the reflector opening 37a designed as a lamp socket. In order to prevent erroneous installation of the lamp in the reflector, one of the three reference lugs 39a has a different shape from the other two reference lugs 39a. The same is, of course, also true for the recesses in the opening 37a designed as a lamp socket, which are matched to the reference lugs 39a. Details of the pressure spring 33c are represented in Figures 7 and 8
Figure 6 shows a fourth illustrative embodiment of the invention, again relating to a single-filament incandescent halogen lamp for installation in the reflector of a motor-vehicle headlight. This lamp has an essentially cylindrical glass lamp bulb 40 with a pinch-sealed lamp-bulb end 40a which is generally referred to as the pinch end 40a. The dome 40b of the lamp bulb 40 is provided with a black light-absorbing coating. The light source used is an incandescent filament 40c, aligned parallel to the axis of the lamp bulb, which is electrically connected to electrical supply leads 41 led out from the pinch end 40a. The lamp bulb 40 is fastened via its pinch end 40a in a metal holder part 42 designed as a fastening ring. The fastening ring 42 is supported by an annular metal support sleeve 43. The support sleeve 43 has four integrally formed welding tabs 43a, which are spot-welded to the fastening ring 42. In addition to the metal fastening ring 42 and the metal support sleeve 43, the lamp cap also has a plastic cap part 44 which is provided with electrical connections 45 of the lamp and in which the support sleeve 43 is anchored. The electrical connections 45 of the lamp are each welded to one of the electrical supply leads 41. The plastic cap part 44 is an injection-moulded part, into which the metal support sleeve 43 is fitted. The support sleeve 43 is equipped with a plurality of integrally formed barbs 43d which irremovably hook into recesses 44a, matched to the barbs 43d inside the plastic cap part 44, when the support sleeve 43 is fitted into the plastic cap part 44. The metal support sleeve 43 furthermore has three integrally formed reference lugs 43b which are angled-off from the support sleeve 43. These reference lugs 43b are arranged equidistantly along a circumference and are used for aligning the incandescent filament 40c and for fastening the lamp in the reflector 47.
The plastic cap part 44 has an annularly extending,
conically designed groove 44b in which a rubber or
silicone gasket 46 is arranged. The gasket 46 bears on
the outside of the reflector wall 47 and seals off the reflector opening 47a designed as a lamp socket. The internal diameter of the gasket 4 6 is accurately matched to the conically designed groove 44b and varies linearly with the gasket height. The plastic cap part 44 is plugged with a casting compound which seals off the lamp cap at the electrical supply leads 41. The three reference lugs 43b, the gasket 46 and a pressure spring 43c, integrally formed below a reference lug 43b on the metal support sleeve 43, are used for fastening the lamp in the lamp socket 47a of the reflector. The lamp cap and the lamp socket 47a form a bayonet connection. In order to install the lamp in the reflector, the lamp is inserted, with the lamp bulb 40 forwards, into the reflector opening 47a designed as a lamp socket, the three reference lugs 43b each engaging through a matched recess in the edge of the opening 47a. The lamp is then rotated in the lamp socket until it meets a stop, so that the reflector wall 47 is clamped between the reference lugs 43b and the gasket 46. The pressure spring 43c bears resiliently on the edge of the reflector opening 47a designed as a lamp socket. In order to prevent erroneous installation of the lamp in the reflector, one of the three reference lugs 43b has a different shape from the other two reference lugs 43b. The same is, of course, also true for the recesses in the opening 47a designed as a lamp socket, which are matched to the reference lugs 43b. Details of the pressure spring 43c are represented in Figures 7 and 8.
In contrast to the first two illustrative embodiments, the plastic cap part 44, provided with the electrical connections 45 of the lamp, here again, as in the third illustrative embodiment, does not engage into the opening 47a of the reflector 47 designed as a lamp socket. However, unlike in the third illustrative embodiment, in this fourth illustrative embodiment the plastic parts are completely left out at the opening 47a, in order to reduce the risk of the insideof the
reflector wall 47 being fogged by the vapours being given off by the plastic lamp parts. In this fourth illustrative embodiment, the plastic reference lugs in illustrative embodiments one to three are replaced by metal reference lugs 43b.
Figures 7 and 8 show two different embodiments of the pressure spring 13c, 23c, 33c, 43c fitted on the metal support sleeve. The embodiment of the pressure spring shown in Figure 7 can be applied to all four above-mentioned illustrative embodiments, while the embodiment of the pressure springs represented in Figure 8 can only be used in illustrative embodiments 1 to 3.
Figure 7 shows a cross-section through the lamp cap, in a plane perpendicular to the axis of the lamp and extending through the pressure spring. The pressure spring 70 is designed as a bent leaf spring and is provided with plane ends 70a and arranged equidistantly along the outer wall of the annular metal support sleeve 71. On one side, the pressure spring 70 is welded via the plane end 70b onto the outer wall of the support sleeve 71, while the other end 70a of the pressure spring 70 bears loosely on the outer wall of the support sleeve 71, so that the end 70a slides on the outer wall of the support sleeve 71 when pressure is exerted on the outwardly bent region 70c of the pressure spring 70. At the pressure spring 70, the annularly designed support sleeve 71 in each case has a plane, that is to say not bent, region 71a on which the ends 70a, 70b of the pressure spring 70 bear. The support sleeve 71 [lacuna] anchored in the plastic cap part 72. The outwardly bent region 70c of the pressure spring 70 bears on the edge of the reflector opening designed as a lamp socket, after the lamp has been installed in the reflector.
Figure 8 shows the second embodiment of the pressure spring, in a section plane through the lamp cap, perpendicular to the axis of the lamp and extending through the pressure spring. Here again, the pressure spring 80 is designed as an outwardly bent leaf spring.
The two ends 80a, 80b of the leaf - spring 80 are each inserted into a hollow recess 82a, 82b between the metal support sleeve 81 and the plastic cap part 82. The outwardly bent region 80c of the leaf spring 80 protrudes from the outer wall of the annular support sleeve 81. When pressure is exerted on the bent region of the leaf spring 80, the leaf-spring ends 80a, 80b slide deeper into the hollow recesses 82a, 82b. The outwardly bent region 80c of the pressure spring 80 bears on the edge of the reflector opening designed as a lamp socket, after the lamp has been installed in the reflector. In all illustrative embodiments, the pressure spring consists of a spring steel.
Figures 9 to 11 show a fifth illustrative embodiment of the invention. This illustrative embodiment of the lamp capped without cement according to the invention is also a single-filament incandescent halogen lamp, to be employed in a motor-vehicle headlight. This lamp has an essentially cylindrical glass lamp bulb 50 with a pinch-sealed lamp-bulb end 50a which is referred to as the pinch end 50a. The dome 50b of the lamp bulb 50 is provided with a black, light-absorbing coating. The light source used is an incandescent filament 50c, aligned parallel to the axis of the lamp bulb and electrically connected to electrical supply leads 51 led out from the pinch end 50a. The lamp bulb 50 is fixed via its pinch end 50a in a metal holder part 52 designed as a fastening ring. The fastening ring 52 is supported by a metal intermediate ring 58 which in provided with three integrally formed, angled-off welding clips 58a. The intermediate ring 58 in turn is laser-welded to a metal support sleeve 53. In addition to the metal fastening ring 52, the intermediate ring 58, and the metal support sleeve 53, the lamp cap also has a plastic cap part 54 which is provided with the electrical connections 55 of the lamp and in which the support sleeve 53 is anchored. The electrical connections 55 of the lamp are each welded to one of the electrical supply leads 51. The plastic cap
part 54 is an injection-moulded part into which the metal support sleeve 53 is injected.
The support sleeve 53 has three integrally formed reference lugs 53a, arranged equidistantly along a circumference . which are used for aligning the incandescent filament 50c and for fastening the lamp in the reflector (not shown in Fig. 9) of the headlight. The reference lugs 53a are angled-off from the support sleeve 53 and lie in a common plane. The welding clips 58a of the intermediate ring 58 are laser-welded to the reference lugs 53a. The intermediate ring 58 provides additional possibilities for alignment in the reference plane defined by the reference lugs 53a.
The plastic cap part 54 has an annularly extending, conically designed groove 54b, in which a rubber or silicone gasket (not shown in Figure 9) is arranged. The gasket bears on the outside of the reflector wall and seals off the reflector opening designed as a lamp socket. The internal diameter of the gasket in this embodiment is also accurately matched to the conically designed groove 54b and varies linearly with the gasket height. A bent leaf spring 90 (Fig. 11), used to fasten the lamp in the headlight, projects through a passage 53b, located below one of the three reference lugs 53a, in the wall of the annular support sleeve 53. The ends 90a, 90b of the leaf spring 90 bear on the inner wall of the support sleeve 53 and on a stop 59a, 59b, each integrally formed on the plastic cap part 54, so that the leaf spring 90 is clamped between these two stops 59a, 59b formed as holders.
The three reference lugs 53a, the gasket arranged in the groove 54b and a pressure spring 90 are used for fastening the lamp in the lamp socket of the reflector. The lamp cap and the lamp socket form a bayonet connection. In order to install the lamp in the reflector, the lamp is inserted, with the lamp bulb 50 forwards, into the reflector opening designed as a lamp socket, the three reference lugs 53a each engaging
through a matched recess in the edge of the opening. The lamp is then rotated in the lamp socket until it meets a stop, so that the reflector wall is clamped between the reference lugs 53a and the gasket as described in the fourth illustrative embodiment and shown in Figure 6. The pressure spring 90 bears resiliently on the edge of the reflector opening designed as a lamp socket. In order to prevent erroneous installation of the lamp in the reflector, the three reference lugs 53a all have different shapes. The same is, of course, also true for the recesses in the opening designed as a lamp socket which are matched to the reference lugs 53a. Details of the pressure spring 90 are represented in Figure 11.
The pressure spring according to the fifth illustrative embodiment is formed as a bent leaf spring. It has two slightly curved ends 90a, 90b which, after being assembled, bear on the inner wall of the annular support sleeve. The leaf spring 90 is fixed in position moreover by two stops 59a, 59b, integrally formed on the plastic cap part 54, on which the ends 90a, 90b meet. As a result the leaf spring 90 is clamped between the stops 59a, 59b (Figure 10) . The leaf spring has a region 90c bulging outwards in bulbous fashion which projects through the passage 53b in the support sleeve 53 after fitting of the leaf spring 90 and bears on the reflector opening designed as the lamp socket after fitting of the lamp in the headlight. In the plan view of Figure 10 the passage 53b is shown in broken lines only, since it is covered by one of the reference lugs 53a. The outwardly bent region 90c of the leaf spring 90 is connected by two inwardly bent regions 90d and 90e to the respective leaf spring ends 90a and 90b. The reference numeral 60 in Figure 10 denotes the passages for the electrical supply leads 51 of the lamp in the plastic cap part 54.
The invention is not restricted to the illustrative embodiments described in detail above. By way of example, the lamp cap according to the invention can also be applied to two-filament incandescent halogen lamps and to
high-pressure discharge lamps, which are intended to be used in motor-vehicle headlights.

WE CLAIM:
1. Electric lamp capped without cement
the lamp having a lamp cap which has a metal holder part (42; 52) in which the bulb (40; 50) of the lamp is fixed,
the lamp cap having a metal support sleeve (43; 53), connected to the metal holder part (42, 52), and a plastic cap part (44; 54) which is provided with the electrical connections (45; 55) of the lamp and in which the metal support sleeve (43; 53) is anchored,
the lamp cap having a plurality of reference lugs (43b; 53a), lying in a plane,
characterized in that the reference lugs (43b; 53a) are made of a metal and are formed integrally with the metal support sleeve (43; 53).
2. Electric lamp capped without cement as claimed in claim 1, wherein
the metal support sleeve (13; 23; 33; 43; 71; 81; 53) is designed annularly, the metal support sleeve (13; 23; 33; 43; 71; 81; 53) is provided with at least one pressure spring (13c; 23c; 33c; 43c; 70; 80; 90).
3. Electric lamp capped without cement as claimed in claim 2, wherein the at least one
pressure spring (13c; 23c; 33c; 43c; 70; 80; 90) is designed as a bent leaf spring.
4. Electric lamp capped without cement as claimed in claim 2, wherein the at least one
pressure spring (13c; 23c; 33c; 43c; 70; 80) is designed as a bent leaf spring, one end
(70b) of the pressure spring (70) being welded to the metal support sleeve (71), the other
end (70a) bearing on the support sleeve (71) such that it can slide, and the leaf spring (70)
bearing resiliently on the edge of the reflector opening (17a; 27a; 37a; 47a) designed as a
lamp socket, after the lamp is fitted.

5. Electric lamp capped without cement as claimed in claim 2, wherein the at least one pressure spring (13c; 23c; 33c; 43c; 70; 80) is designed as a bent leaf spring, the ends of the leaf spring (80) each being arranged in a recess (82a, 82b) between the metal support sleeve (81) and the plastic cap part (82), so that the leaf spring (86) bears resiliently on the edge of the reflector opening (17a; 27a; 37a; 47a) designed as a lamp socket, after the lamp is fitted.
6. Electric lamp capped without cement as claimed in claim 1 and 3, wherein the plastic cap part (54) has holders (59a; 59b) between which the ends (90a; 90b) of the at least one leaf spring (90) are clamped, and the support sleeve (53) has a passage (53b) in which the at least one leaf spring (90) engages.
7. Electric lamp capped without cement as claimed in claim 6, wherein:
the ends (90a; 90b) of the at least one leaf spring (90) bear on the inner wall of the support sleeve (53),
the at least one leaf spring (90) has an outwardly bent region (90c) which engages in the passage (53b),
the at least one leaf spring (90) has two inwardly bent regions (90d, 90e) which connect the outwardly bent region (90c) to one of the leaf spring ends (90a, 90b) each.
8. Electric lamp capped without cement as claimed in claim 3, wherein the at least one pressure spring (13c; 23c; 33c; 43c; 70; 80; 90) is made of a spring steel.
9. Electric lamp capped without cement as claimed in claim 1, wherein the support sleeve (13; 23; 33; 43; 71; 81; 53) is made of steel or German silver.
10. Electric lamp capped without cement as claimed in claim 1, wherein the holder part (52)
is connected to the metal support sleeve (53) via an intermediate ring (58) which is
provided with integrally formed, angled-off welding clips (58a), by welding the welding

clips (58a) of the intermediate ring (58) to the reference lugs (53 a) of the metal support sleeve (53).
11. Electric lamp capped without cement as claimed in claim 1, wherein the plastic cap part (14; 24; 34; 44; 54) has an annularly extending conically designed groove (14b; 24b; 34b; 44b; 54b) for receiving a gasket (16; 26; 36; 46).
12. Electric lamp capped without cement as claimed in claim 11, wherein the internal diameter of the gasket (16; 26; 36; 46) is accurately matched to the conically designed groove (14b; 24b; 34b; 44b; 54b) and varies linearly with the height of the gasket.
13. Electric lamp capped without cement and reflector,
the reflector being provided with an opening (47a) designed as a lamp socket and made in the reflector wall (47),
the lamp having a lamp cap which has a metal holder part (42; 52) in which the bulb (40; 50) of the lamp is fixed,
the lamp cap having a metal support sleeve (43, 53) connected to the metal holder part (42; 52) and a plastic cap part (44; 54) which is provided with the electrical connections (45; 55) of the lamp and in which the metal support sleeve (43; 53) is anchored,
the lamp cap having a plurality of reference lugs (43b; 53a), lying in a plane, which are used for holding and for correct installation of the lamp in the reflector,
wherein the reference lugs (43 b, 53 a) are made of a metal and are formed integrally with the metal support sleeve (43; 53), the reference lugs (43b; 53a) engaging into the reflector opening (47a) designed as a lamp socket.
14. Electric lamp capped without cement and reflector as claimed in claim 13, wherein
the metal support sleeve (13; 23; 33; 43; 71; 81; 53) is designed annularly,

the diameter of the metal support sleeve (13; 23; 33; 43; 71; 81; 53) is matched to the engagement diameter of the reflector opening (17a; 27a; 37a; 47a) designed as a lamp socket,
the metal support sleeve (13; 23; 33; 43; 71; 81; 53) is provided with at least one pressure spring (13c; 23c; 33c; 43c; 70; 80; 90) which bears on the reflector wall (17, 27; 37; 47) after the lamp has been fitted in the reflector at the opening (17a; 27a; 37a; 47a) designed as a lamp socket.
15. Electric lamp capped without cement substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

Documents:

1907-DEL-2005-Abstract-(29-04-2011).pdf

1907-del-2005-abstract.pdf

1907-del-2005-Claims-(01-05-2014).pdf

1907-del-2005-Claims-(19-02-2014).pdf

1907-DEL-2005-Claims-(29-04-2011).pdf

1907-del-2005-claims.pdf

1907-del-2005-Correspondence Others-(01-05-2014).pdf

1907-del-2005-Correspondence Others-(13-11-2013).pdf

1907-del-2005-Correspondence Others-(19-02-2014).pdf

1907-DEL-2005-Correspondence Others-(29-04-2011).pdf

1907-del-2005-correspondence-others.pdf

1907-DEL-2005-Description (Complete)-(29-04-2011).pdf

1907-del-2005-drawings.pdf

1907-DEL-2005-Form-1-(29-04-2011).pdf

1907-del-2005-form-1.pdf

1907-del-2005-form-18.pdf

1907-DEL-2005-Form-2-(29-04-2011).pdf

1907-del-2005-form-2.pdf

1907-del-2005-Form-3-(19-02-2014).pdf

1907-DEL-2005-Form-3-(29-04-2011).pdf

1907-del-2005-form-3.pdf

1907-del-2005-form-5.pdf

1907-del-2005-GPA-(19-02-2014).pdf

1907-DEL-2005-GPA-(29-04-2011).pdf

1907-del-2005-gpa.pdf

1907-DEL-2005.pdf

1907-del-2005description (complete).pdf

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Patent Number

260569

Indian Patent Application Number

1907/DEL/2005

PG Journal Number

19/2014

Publication Date

09-May-2014

Grant Date

08-May-2014

Date of Filing

20-Jul-2005

Name of Patentee

PATENT - TREUHAND-GESELLSCHAFT FUR ELEKTRISCHE GLUEHLAMPEN MBH.

Applicant Address

HELLABRUNNER STR. 1, 81543 MUNCHEN, GERMANY.

Inventors:

#	Inventor's Name	Inventor's Address
1	PETER HELBIG	ROEMERSTR. 20, 89567 SONTHEIM, GERMNAY
2	HERMANN STEINER	ELCHWEG 29, 89542 HERBRECHTINGEN, GERMANY.

PCT International Classification Number

H01J61/36

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	19600714.3	1996-01-11	Germany