WO2010060830A1

WO2010060830A1 - Integrated gas discharge lamp and method, containing incremental frequency increase, for operating an integrated gas discharge lamp

Info

Publication number: WO2010060830A1
Application number: PCT/EP2009/065321
Authority: WO
Inventors: Bernhard Siessegger
Original assignee: Osram Gesellschaft mit beschränkter Haftung
Priority date: 2008-11-28
Filing date: 2009-11-17
Publication date: 2010-06-03
Also published as: TW201031273A

Abstract

The invention relates to an integrated gas discharge lamp and to a method for operating an integrated gas discharge lamp (5), wherein a gas discharge lamp burner (50) and operating electronics for the gas discharge lamp burner (50) are integrated in a lamp, wherein the operating frequency of the integrated gas discharge lamp (5) is increased starting from a lower limit frequency at a low cumulative burning time (tk) over the burning time of the gas discharge lamp burner (50) of the integrated gas discharge lamp (5) to a final value at a cumulative burning time that is close to the specified lifetime of the gas discharge lamp burner (50) of the integrated gas discharge lamp (5).

Description

description

INTEGRATED GAS DISCHARGE LAMP AND METHOD, INCLUDING STEP-BY-STEP FREQUENCY HOLDING, FOR OPERATING AN INTERGRATED GAS DISCHARGE LAMP

Technical area

[2] The invention is based on an integrated gas discharge lamp in which a gas discharge lamp burner and an operating electronics for the gas discharge lamp burner are integrated in a lamp and a method for operating an integrated gas discharge lamp.

State of the art

The invention is based on an integrated gas discharge lamp in which a gas discharge lamp burner and an operating electronics for the gas discharge lamp burner are integrated in a lamp and a method for operating an integrated gas discharge lamp according to the preamble of the main claim.

[4] Gas discharge lamps tend to flicker with extended burning time. This results from a larger electrode spacing, on the one hand, and from a deformed and fissured electrode tip, for example, which no longer guarantees a clean arc approach. The larger electrode gap decreases the current, and the electrode is heated less, which is reflected in an increased flickering.

[0005] EP 0 792 570 B1 discloses an operating method for a gas discharge lamp which is intended to ensure a uniform electrode temperature. The document proposes a variation of the full-bridge frequency during low-frequency square-wave operation during startup and normal operation. The frequency is thereby using a stored in the microcontroller function of electrode temperature and lamp current determined. The electrode temperature is derived from a model. This method is intended to prevent the lamp from extinguishing immediately after the commutation, since the anode always has a sufficiently high temperature before commutation in order to be able to emit sufficient electrons after the commutation. Disadvantage of the method is the complex calculation of the electrode temperature according to the model. In addition, the electrode spacing is not included in the model.

task

It is an object of the invention to provide an improved method for operating an integrated gas discharge lamp (5), in which a gas discharge lamp burner (50) and an operating electronics for the gas discharge lamp burner (50) are integrated in a lamp.

[8] It is also an object of the invention to provide an improved integrated gas discharge lamp which carries out the method.

Presentation of the invention

[9] The solution to the problem with respect to the integrated gas discharge lamp is provided by an integrated gas discharge lamp, which carries out a method described below.

The solution of the problem with respect to the method is carried out according to the invention with a method of operation an integrated gas discharge lamp, in which a gas discharge lamp burner and operating electronics for the gas discharge lamp burner are integrated in a lamp, wherein the operating frequency of the integrated gas discharge lamp from a lower limit frequency at a low cumulative burning time over the burning time of the gas discharge lamp burner of the integrated gas discharge lamp to a final value is increased at a cumulative burn time that is close to the specified life of the gas discharge lamp burner of the integrated gas discharge lamp. Increasing the frequency also increases the minimum electrode temperature of the gas discharge lamp torch, which in turn significantly reduces the likelihood of flicker.

[11] If, in a first embodiment, the operating frequency remains constant at a lower cut-off frequency up to a cumulative burn time of about 10% -20% of the nominal life of the gas discharge lamp burner (50), then to 40% -60% successively during the cumulative following burn time 0.5 Hz / h is increased to a first upper limit frequency to stay from then at the first upper cutoff frequency, then an optimum electrode temperature is ensured at which a flicker no longer occurs. Preferably, the operating frequency remains constant at about 400 Hz up to a cumulative burning time of about 500 h, and then continuously increases by 0.5 Hz / h to about 900 Hz during the cumulative burning period of about 500 h to about 1500 h. and then stay at about 900 Hz. In a second embodiment, a method for operating an integrated gas discharge lamp is proposed, which operates with the following steps.

1. increasing the operating frequency from a cumulative first burning time by a predetermined first frequency,

2. wait for a predetermined time,

3. increasing the operating frequency by a predetermined first frequency,

4. Repeat steps 2 and 3 n times Repeatedly increase the frequency by discrete

Steps, the method is well implemented in a digital logic, which saves costs and executable with modern circuitry. Here, when the cumulative first burning time is between 10% and 20% of the rated life of the gas discharge lamp burner, the predetermined time is 1h-20h, the first frequency is between 1Hz and 50Hz, and n = 16 ... 256 so the process is especially safe. In a particularly efficient embodiment, the operating frequency always decreases after a cumulative burning time of 2097152 s

Sequence of 32768 s 128 times increased by 4 Hz each up to a final value of 912 Hz. This can be done particularly well in digital binary logic, since the number logic consists of powers of two.

In a particularly simple embodiment, the operating frequency is increased from a cumulative second burning duration in one step from a lower cutoff frequency to a first upper cutoff frequency. This is a particularly simple and cost-effective variant of the method, which can also significantly reduce the tendency to flare. Particularly preferred is the cumulative second firing time between 5% and 20% of the nominal life of the gas discharge lamp burner, the lower cutoff frequency between 100 Hz and 500 Hz, and the first upper cutoff frequency between 600 Hz and 900 Hz. These values achieve the best results in a xenon high pressure discharge lamp for automobile headlights , If the operating frequency is increased from a frequency of 400 Hz to a frequency of 800 Hz in one step from a cumulative burning time of 1048576 s in one step, the method can again be carried out particularly efficiently by means of a digital binary logic.

[14] In a further preferred embodiment, the operating electronics have a detection circuit for detecting flickering of the arc of the gas discharge lamp burner, and the following steps are carried out starting from a cumulative burning time of the gas discharge lamp burner of about 16% of the rated service life:

Stepwise increasing the operating frequency of the gas discharge lamp burner from the lower limit frequency to the first upper limit frequency,

Measurement of the flicker intensity of the arc of the gas discharge lamp burner at the selected operating frequency,

Storing the measured flicker intensity and the correlated operating frequency,

- Setting the operating frequency to the frequency with the lowest flicker intensity.

Thus, a flicker can be well suppressed even with difficult lamps.

[15] In a further preferred embodiment, the operating electronics has a detection circuit for Detecting flickers of the arc of the gas discharge lamp burner, and performs the following steps repeatedly from a cumulative burning time of the gas discharge lamp burner of about 16% of the rated life:

Stepwise increasing the operating frequency of the gas discharge lamp burner from the lower limit frequency up to a second upper limit frequency,

- As soon as the Flackerintensität falls below a predetermined threshold setting the operating frequency to the current frequency and termination of the process. This is a simplified version of the previous method that works equally well and can be done with a simpler, low memory logic. In this case, the second upper limit frequency is preferably between 600 Hz and 900 Hz. In a further embodiment, the second upper limit frequency is tripled in the event of a failure to fall below the predetermined threshold of flicker intensity. This also helps to prevent lamp flicker even with lamps approaching their end of life.

[16] Further advantageous developments and refinements of the integrated gas discharge lamp according to the invention and of the method according to the invention emerge from further dependent claims and from the following description.

Short description of the drawing (s) [17] Further advantages, features and details of the invention will become apparent from the following description of exemplary embodiments and with reference to the drawings, in which the same or functionally identical elements are provided with identical reference numerals. Showing:

1 is a sectional view of an integrated gas discharge lamp according to the invention in a first embodiment,

FIG. 2 is an exploded view of the mechanical components of the integrated gas discharge lamp in the first embodiment; FIG.

3 shows a sectional view of an integrated gas discharge lamp according to the invention in a second embodiment,

4 shows a perspective view of an integrated gas discharge lamp according to the invention in a second embodiment,

5 is a view of the interface headlamp / gas discharge lamp,

6 shows a detailed view of the electrical contacting,

7 shows a detailed view of the mechanical contacting,

8 is a sectional view of a third embodiment of the integrated gas discharge lamp, 9 shows a perspective view of an integrated gas discharge lamp according to the invention in a fourth embodiment,

10 shows a perspective view of an ignition transformer of the integrated gas discharge lamp,

11 is a perspective view of the upper part of the ignition transformer,

12 is a perspective view of the lower part of the ignition transformer,

13 is a perspective view of the lower part of the ignition transformer with visible secondary winding,

14 is an exploded view of the ignition transformer in a second round embodiment,

15 is a sectional view of the ignition transformer in a second round embodiment,

16 is an exploded view of the ignition transformer in a third round embodiment with two-winding primary winding,

17 is a sectional view of the ignition transformer in a third round embodiment with two-winding primary winding,

18a is a schematic circuit diagram of a single-ended pulse ignition according to the prior art, 18b is a schematic circuit diagram of a symmetrical Impulsekündgerätes according to the prior art,

19 is a schematic diagram of an asymmetric see pulse ignition device,

20 is a schematic circuit diagram of an extended circuit of the integrated gas discharge lamp,

21 is a sectional view of the gas discharge lamp burner of the integrated gas discharge lamp with the base construction,

22 shows a diagram of the operating frequency of the gas discharge lamp burner over its burning time,

FIG. 23 is a circuit topology for a straight arc discharge operation in a first embodiment; FIG.

24 is a circuit topology for a straight arc discharge operation in a second embodiment;

25 is a circuit topology for a straight arc discharge operation in a third embodiment;

26 shows a circuit topology for a simplified operation of a DC-DC converter,

FIG. 27 is a graph showing the functional relationship between the normalized target burn power and the cumulative weighted burn time of the gas discharge lamp burner. FIG. 28 is a graphical representation of the weighting function γ,

29 is a graphical representation of the function α,

30 is a graphical representation of the normalized nominal luminous flux as a function of the normalized cumulative burning time of the gas discharge lamp burner,

31 shows a sectional view of an integrated gas discharge lamp according to the invention in a fifth embodiment,

32 shows a flow chart of a variant of a first embodiment of a method for operating an integrated gas discharge lamp,

33 is a flow chart of another variant of the first embodiment of the method for

Operating an integrated gas discharge lamp,

34 is a flow chart of a second embodiment of a method for operating an integrated gas discharge lamp.

Preferred embodiment of the invention

Mechanical integration 1 shows a sectional view of a first embodiment of the integrated gas discharge lamp 5. In the following, a gas discharge lamp 5, which has integrated both the ignition electronics and the operating electronics in the lamp base of the gas discharge lamp 5, is referred to as the integrated gas discharge lamp 5. The integrated gas discharge lamp 5 therefore has no specific lamp interface to the outside, but can be connected directly to common and widespread power grids. In one embodiment, as an automobile headlamp, the interface of the integrated gas discharge lamp 5 is thus the conventional 12 V supply of the automotive on-board network. In another embodiment, as an automotive lamp, the interface of the integrated gas discharge lamp 5 may also be a future 42V supply of a modern automotive electrical system. However, the integrated gas discharge lamp 5 can also be designed to be connected to the high-voltage electrical system of an electric car with a battery voltage of eg 48V, 96V, 120V up to exemplary 360V. Furthermore, the integrated gas discharge lamp can be designed to work on an emergency power supply with a battery-backed low-voltage network. Likewise, this lamp can be used in low-voltage island networks, as used for example in mountain huts. Even conventional low-voltage systems, in which low-voltage halogen lamps used to date, are conceivable as an application here. Even in portable such as flashlights such a lamp is an advantage, since no wiring between the lamp and the control gear is necessary. The fact that the cable is omitted eliminates additional costs, cabling. wall and unnecessary sources of error. As an integrated gas discharge lamp 5, a gas discharge lamp is thus meant below, which has integrated all necessary for the operation electronics in the lamp itself, so that it can be connected directly to a conventional power supply.

A lamp burner 50 is supported by a metal bracket 52 which is attached to 4 retaining plates 53. The retaining plates 53 are cast or injected into a lamp cap 70. The lamp cap 70 is preferably made of plastic, and is manufactured by an injection molding method or a casting method. In order to improve the electrical shield, the plastic of the lamp cap 70 may be electrically conductive or metallized. Particularly advantageous is a metallization of the lamp cap on the outside, consequently on the ignition and operating electronics 910, 920 side facing away. In addition to a metallization, the encapsulation of metallic conductors or a metallic mesh is also possible, so that an electrically conductive skin located in the wall of the lamp cap 70 is formed. If no conductive or metallized plastic is used, the plastic base is enclosed by an electrically conductive housing 72 made of a conductive material, such as metal. The metal may be, for example, a corrosion-protected sheet iron or even a non-ferrous metal such as aluminum, magnesium or brass. At the burner end of the electrically conductive housing 72 sits a sealing ring 71, commonly referred to as an O-ring, which accomplishes a seal towards the reflector. By this measure, a dense Headlight system can be constructed without having to install the lamp completely in a sealed headlight. The fact that the lamp is located on the outside of the headlamp, the cooling of a base located in the ignition and operating electronics 910, 920 is significantly better and easier than with a conventional structure in which the gas discharge lamp 5 is installed in a dense headlight, in which only one weak cooling convection can take place. The approximately stationary air within the described, dense headlamp causes a so-called heat accumulation, which leads to significantly higher temperatures of the operating electronics, as in the proposed embodiment, in which the lamp is on the side facing away from the light exit surface side into the open, for example in the engine compartment ,

The base 70 is closed on the lamp burner 50 side facing away from a base plate 74. The base plate 74 is preferably made of a thermally and electrically good conductive material such as aluminum or magnesium. In order to establish a mechanical connection with the base 70 and an electrical connection to the electrically conductive housing 72, this has a plurality of tabs 722 on the side facing away from the lamp burner 50, which are flanged onto the base plate 74 during assembly of the integrated gas discharge lamp 5, and make the necessary connections. Among other things, this type of connection technology lamp torch 50, 910 ignition electronics and 920 operating electronics are inseparably connected to an integrated gas discharge lamp 5. This has the advantage for the motor vehicle manufacturer that in the Contrary to conventional systems consisting of control gear and gas discharge lamp, the integrated gas discharge lamp 5 from the logistics as well as the assembly is only one part, the lower complexity leads to reduced costs and a likelihood of confusion between components with the same function but different Design, such as different product versions of the operating devices is eliminated. For the end customer, such as the vehicle owner, this results in the advantage that the reduced complexity significantly simplifies and speeds up the replacement of a defective integrated gas discharge lamp over the prior art, facilitates troubleshooting and less knowledge and skills required to perform a lamp replacement. The elimination of cables and connectors between components also reduces costs, increases reliability and reduces weight.

The base plate is preferably made of die-cast aluminum or die-cast magnesium. This is an inexpensive as well as mechanically and electrically high-quality variant. An electrically good conductive connection between the at least superficially electrically conductive lamp base 70 or the electrically conductive housing 72 and the likewise electrically conductive base plate 74 is particularly required for a good electromagnetic shielding. This shield prevents the interference of adjacent electrical or electronic assemblies. In addition, the shielding ensures that the assemblies do not negatively affect the function of ignition and drive electronics 910, 920 have. Between the base plate 74 and the base 70, a sealing ring 73 is arranged, which ensures a water and airtight connection between the base 70 and the base plate 74. In an alternative embodiment, the base 70 and the base plate 74 is formed such that both parts are latched into each other and in detent position simultaneously one or more contact points between the electrically conductive housing 72 and the base plate 74 are made to a good connection for the electrical

Shielding to generate. Again, between the base and base plate, a sealing ring is arranged, which ensures the tightness of the base on the gas discharge lamp burner 50 side facing away. Inside the base 70, two levels are provided, which receive the ignition and operating electronics. A first smaller plane closest to the lamp burner 50 receives the ignition electronics 910 with the ignition transformer 80. The construction of the ignition transformer 80 will be discussed later. A second, larger level accommodates the operating electronics 920 necessary for the operation of the discharge lamp burner 50. The ignition and the operating electronics can be located on any suitable type of circuit board, also called circuit board. Conventional PCBs, metal-core PCBs, LTCC technology PCBs, thick-layered, oxidized or coated metal plates, MID or MID hot-stamping PCBs, or any other suitable technology for producing temperature-resistant printed circuit boards are possible. The electronic components and components that make up the ignition and operating electronics can each are located on the top and bottom and inside the two circuit boards. For reasons of clarity, in FIG. 1, apart from the transformer 80, no further electronic components or components are shown on the printed circuit board. Unless the

PCB for the ignition electronics 910 and the circuit board for the operating electronics 920 made of the same material, they can be advantageously manufactured on the same benefit. In this case, bridges can be fitted between the boards, which serve as electrical connections between the boards during separation and introduction into the lamp cap 70. As bridges, for example, single wires, ribbon cables or rigid-flexible circuit boards can be used. The electrical connection of the two printed circuit boards is designed so that it survives a change in distance between the two circuit boards of the ignition and operating electronics by thermal expansion, in particular by a thermal cycle stress, unscathed. For this purpose, for example, the wires are to be provided with sufficient length and appropriate installation within the housing. Alternatively, for example, one or more male and female headers may be used which are sized and arranged to permit thermal expansion in the direction of the longitudinal axis of the gas discharge lamp burner of the two circuit boards and still provide electrical connection in all cases. For this purpose, for example, the pins of the pin header are arranged perpendicular to the respective circuit board surface and the insertion length of the sockets is dimensioned such that they provide more travel for the pins than These require due to the thermal expansion within the sockets.

The circuit board for the ignition electronics 910 has on the side facing the operating electronics on an electrically conductive shielding to disturbances caused by the high voltage in the ignition electronics, as far as possible to keep away from the operating electronics. In the case of a metal or metal core board, this surface is inherently present; in the case of other board materials, preferably a copper surface or the like is applied to this side. If a metal core board is used, it can also be used to cool the ignition transformer 80, which is exposed to a particularly high thermal load due to its proximity to the gas discharge lamp burner 50. An electrically conductive shielding surface between the ignition electronics 910 and the operating electronics 920 may alternatively be effected by a metallic sheet, which is introduced between the two printed circuit boards and advantageously electrically conductively connected to the electrically conductive housing 72. If this shielding surface also serves to cool the ignition transformer 80, then it is advantageous if the metallic sheet also has a good thermal connection, for example, by a heat conducting foil or heat conducting paste to the electrically conductive housing 72.

The printed circuit board for the operating electronics 920 is clamped between the base 70 and the base plate 74. The printed circuit board for the operating electronics 920 has on its circumference in each case on the top and bottom of a circumferential ground trace, so-called Masserin- ge, which are electrically connected to each other due to vias. These vias are commonly referred to as vias, and are electrical contacts that run through the circuit board. These Masseringe put through the

Einklemmung between the base 70 and the base plate 74 an electrical contact to the base plate 74 ago, whereby the ground connection of the operating electronics 920 is ensured to the electrically conductive housing 72 via the flanged tabs 722.

2 shows an exploded view of the mechanical components of the integrated gas discharge lamp 5 in the first embodiment. Here the pedestal is square, but in principle it can also have many other suitable shapes. Particularly favorable further embodiments would be round, hexagonal, octagonal or rectangular. In order to determine the outer contour of the embodiment, a section perpendicular to the longitudinal axis of the gas discharge lamp burner 50 is carried out by the housing part containing the electronics, and the resulting outer contour is considered, wherein roundings at the edges of the housing are negligible. In the case of the first embodiment shown in FIGS. 1 and 2, depending on whether the selected cut surface is closer to the ignition electronics 910 or closer to the operating electronics 920, there are two squares. The first embodiment is therefore a quadratic embodiment. The first resulting outer contour in the vicinity of the ignition electronics 910 is smaller than the second, which is essentially due to the fact that the circuit board of the ignition electronics 920 are low. However, this does not necessarily have to be the case and an embodiment in the two outer contours have the same size and consequently there is only a single outer contour is possible. Also, the two have to

Geometries of the outer contours in the different areas may not be identical. In particular, in the field of ignition electronics small, round and larger in the field of operating electronics, hexagonal outer contour appears as a particularly advantageous embodiment.

The board for the operating electronics 920 is, as already stated above, clamped between the base 70 and the base plate 74. The sealing ring 73, like the printed circuit board for the operating electronics 920, lies between the base 70 and the base plate 74, and is arranged outside the circuit board for the operating electronics 920.

3 shows a sectional view of a second embodiment of the integrated gas discharge lamp 5. The second embodiment is similar to the first embodiment, therefore, only the differences from the first embodiment will be described. In the second embodiment, the ignition electronics 910 and the operating electronics 920 are arranged in a common plane on a printed circuit board as overall operating electronics 930. By virtue of this measure, the base of the gas discharge lamp 5 according to the invention can be made flat, whereby a headlight which uses this gas discharge lamp 5 likewise has less depth. The ignition transformer 80 sits centrally under the gas discharge lamp burner. In this case, the center of the ignition transformer 80 is preferably in the longitudinal axis of the gas discharge lamp burner 50. The power supply for the sockelnahe gas discharge lamp burner electrode protrudes into the central part of the ignition transformer inside. The ignition transformer is not mounted on the printed circuit board, but sits with its end remote from the gas discharge lamp burner at approximately the same level as the side of the printed circuit board remote from the gas discharge lamp burner. The printed circuit board of the overall operating electronics 930 is recessed at this point, so that the ignition transformer 80 is inserted into the circuit board of the overall operating electronics 930. To improve the electromagnetic compatibility, the housing, for example, by webs of aluminum sheet or mu-metal, be provided with walls and chambers and thereby carried an electrical, magnetic and electromagnetic shielding of different circuit parts against each other and against the environment. The shielding can also be achieved by other measures, in particular the

Formation of cavities in the base plate 74 and in the lamp cap 70 as part of the injection molding process easily feasible.

The remaining cavities within the housing of the integrated gas discharge lamp 5, in particular around the

Ignition transformer 80 and on both sides of the total operating electronics 930, are filled with potting compound. This has several advantages, such as electrical flashovers, in particular by the high voltage generated by the ignition transformer safely prevented, ensures good cooling of the electronics, as well as a mechanically very robust unit that resists environmental influences such as moisture and high accelerations very well. In particular, in order to reduce the weight, however, only a partial encapsulation, for example in the region of the ignition transformer 80, can be realized.

Fig. 8 shows a third embodiment of the integrated gas discharge lamp 5 according to the invention. The third embodiment is similar to the first embodiment, therefore, only the differences from the first embodiment will be described. In the third embodiment, the base plate 74 is provided on its outside with cooling fins. It is also conceivable that the lamp base 70 and the electrically conductive housing 72 are each provided with cooling fins. In addition, the function of the printed circuit board of the operating electronics 920 is also fulfilled by the base plate, as this has on its inside electrically non-conductive areas, such as areas of anodized aluminum, which are provided with conductive structures, such as printed conductors in thick film technology, and those with the components the total operating electronics electrically conductive, for example by soldering, are connected. By this measure, the operating electronics 920 cooled particularly well, since it is applied directly to a heat sink. The cooling fins are preferably designed such that natural convection in the installation position of the integrated gas discharge lamp 5 is favored. If the integrated gas discharge lamp 5 can be operated in various installation positions, then the cooling

Surface also be designed accordingly and For example, round, hexagonal, square or rectangular fingers, so that a natural Konvek- tion in several spatial directions can take place. As in the first embodiment, the ignition electronics 910 fit on an overlying printed circuit board, and are electrically connected to the operating electronics 920 by suitable measures. This can be accomplished by spring contacts or plug contacts, but also by running in the socket traces or on the inside of the base printed conductors, which are connected to the ignition electronics 910 and the operating electronics 920.

9 shows a fourth embodiment of the integrated gas discharge lamp 5 according to the invention. The fourth embodiment is similar to the second embodiment, therefore, only the differences from the second embodiment will be described. In the fourth embodiment, the base plate 74 is realized by a on the inside, and thus, as in the previous embodiment, also on one side, stocked metal core board. However, the base plate 74 is not a plate as in Fig. 4 but a base cup with raised side walls. For reasons of clarity, the baseplate is therefore referred to below as a socket cup. The base cup may also consist of a thermally highly conductive material. Particularly suitable are metal alloys, which can be well formed, for example by deep drawing. Also suitable is a thermally highly conductive plastic, which can be brought into shape by injection molding. The base 70 with the reference ring 702 and the reference knobs 703 is in this embodiment essentially of a hexagonal plate on which the burner within the reference ring is adjusted and fixed. The base cup houses the total operating electronics 930, which fits on a separate circuit board or on the inner bottom of the base cup. At the power supply lines 56, 57 of the gas discharge lamp burner 50 plug contacts are mounted, which engage in the assembly of the socket cup and the base 70 in corresponding mating contacts of the Sockelbe- cher and establish a reliable contact.

Are the base cup and the base 70 made of metal, the two parts can be connected by crimping as a coffee can or tin. But it can also, as shown in FIG. 9, only a plurality of flaps of the base cup are crimped onto the base in order to produce a mechanically and electrically good connection. For the preparation of the compound but also the known soldering and welding methods can be used.

If the base cup and the base 70 are made of plastic, then the connection can preferably be effected by ultrasonic welding. This results in a reliable and firm connection, which in the case of a conductive synthetic material also leads to a conductive connection. However, the connection can also take place by means of corresponding latching, for this purpose corresponding latching lugs or depressions are then to be provided on the base cup or the base 70. In the following, the diameter (D) and the height (h) of the integrated gas discharge lamp 5 are to be defined largely independently of the geometry, in order to be able to make a simpler description. Under the height (h) of the integrated gas discharge lamp, the maximum distance of the reference plane, which will be discussed in more detail below, to the burner facing away outside of the base plate (74) understood. The diameter (D) is understood to mean the longest distance within the integrated gas discharge lamp, the plug lying within an arbitrary plane, this plane extending parallel to the reference plane.

The following table shows some geometric variables of different embodiments of the fourth embodiment of the gas discharge lamp 5 shown in FIG. 9:

Diameter length or height h volume mass D / h

A. 50W lamp

100 35 275 510 2.86

B. 35W lamp

100 25 196 178 4.00

C. 25W lamp, standard version

70 25 99 139 2.80

D. 18W lamp, variant super flat

100 15 120 168 6.67

E. 45W lamp, variant coffee can

40 50 63 52 0.80

F. 7W lamp, for use in flashlight

40 35 44 36 1, 14 The listed in the table electrical power from 7 W to 50 W of different configurations relate to the nominal electric power of the gas discharge lamp burner. Different geometries and sizes of the same type gas discharge lamp burner are used.

As can be clearly seen in Fig. 4, the lamp base of the integrated gas discharge lamp 5 according to the second and fourth embodiments has a hexagonal shape, which brings several advantages. On the one hand, the integrated gas discharge lamp 5 is so easy to grasp to use it at its destination. On the other hand, the utility of integrated circuit integrated-circuit electronics board 930 may be such that only a small amount of waste occurs and good cost efficiency becomes possible. Due to the flat design of the base, a very short-built headlights can be designed, which is particularly advantageous in modern motor vehicles. The point-symmetric hexagonal shape enjoys in this application all the advantages of a round shape, but without having their disadvantages.

As shown in FIGS. 3 and 4, on one side of the base 70 of the lamp, contacts 210, 220 protrude radially outward from the base to the longitudinal axis of the gas discharge lamp burner 50. They serve the electrical contacting of the integrated gas discharge lamp 5 with a headlight. These contacts are encapsulated in the manufacture of the lamp cap 70 in a plastic injection molding process. This has the advantage that no special plug system is required, but nevertheless the water and airtight encapsulation, as already described above, can be ensured.

Headlamp Interface The interaction between integrated gas discharge lamp 5 and headlamp 3 is shown in FIG. The gas discharge lamp 5 in the second embodiment has a special electrical interface through which it is supplied with electric power. The electrical interface is designed such that upon insertion of the gas discharge lamp 5 in a headlight 3, this is not only mechanically connected to the headlight 3, but also at the same time electrically. A similarly constructed interface is also used in modern halogen incandescent lamps for automobile headlamps, and e.g. sold by Osram under the name "Snap Lite." Will the integrated

Gas discharge lamp 5 thus used in a reflector or headlight, so all required for proper operation mechanical and electrical contacts are connected to their present in the headlight 3 corresponding mating contacts in the process of insertion. The base 70 has at its interface to the headlight 3 from a reference ring 702 emerging nubs 703, which define a reference plane. A detailed illustration is shown in FIG. 7. These three nubs are at the onset of the integrated gas discharge lamp 5 on the corresponding counterpart of the headlamp 3. The electrodes or the discharge arc of the gas discharge lamp burner 50 are adjusted in the manufacturing process of the integrated gas discharge lamp 5 with respect to the reference plane. As a result, the arc of the integrated gas discharge lamp 5 takes in the reflector at her Insert a defined position in the headlamp, which allows a precise optical image. The insertion into the headlamp takes place in the second embodiment according to FIGS. 3 & 4 by inserting the tabs laterally projecting from the reference ring 704 through the reflector bottom of a reflector 33 of the headlamp 3. Thereafter, the integrated gas discharge lamp 5 is rotated relative to the reflector 33, whereupon the knobs 703, which are attached to the base-side surface of the tabs 704, pull the integrated gas discharge lamp inwards and engage at the end of the rotation in designated reference surfaces on the reflector base. The sealing ring 71 is thereby pressed together and holds the system in tension so that the knobs 703 are located opposite to those in the reflector base

Reference surfaces are pressed. Thus, the position of the integrated gas discharge lamp 5 and thus of the discharge arc of the gas discharge lamp burner 50 relative to the reflector 33 is precisely adjusted and fixed. The high repeat accuracy of the mechanical positioning of typically better than 0.1 mm in all three spatial directions of the described headlight interface allows the realization of an optically excellent headlamp system. Such a headlamp system can be found in particular in a motor vehicle application, after it is characterized in the corresponding embodiment by a pronounced and well-defined cut-off.

For this purpose, a suitable headlight 3 has a light-guiding means in the form of a reflector 33, a receptacle for the integrated gas discharge lamp 5, and a carrier part 35 on, wherein on the support part with a mating contacts for the electrical contacts 210, 220, 230, 240 of the integrated gas discharge lamp 5 provided connection element is arranged. The electrical contacts 210, 220, 230, 240 of the integrated gas discharge lamp 5 protrude radially outward from the lamp cap 70 to the longitudinal axis of the gas discharge lamp burner 50. They serve to supply the total operating electronics 930 with electrical energy. After mounting the integrated gas discharge lamp 5 in the headlamp by a mounting operation based essentially on a mating motion followed by a rightward rotation, its contacts 210, 220, 230, 240 are disposed in the slots 351, 352 of the terminal 35, as in FIG the detail drawing in Fig. 6 can be seen. These slots 351, 352 are the slots for the electrical mating contacts 350 to the contacts 210, 220, 230, 240 of the integrated gas discharge lamp 5. This eliminates the provided with connecting cables plug for contacting the integrated gas discharge lamp 5 in the headlight according to the state of the technique. In particular, the electrical contacts of the integrated gas discharge lamp 5 when inserted into the headlight are contacted directly with their mating contacts 350 of the connection element on the carrier part 35. This will reduce the mechanical load on the electrical

Connections reduced by freely oscillating cables. Furthermore, the number of required connection cables per headlamp is reduced, thereby reducing the risk of confusion during manufacture. In addition, this measure also allows a higher degree of automation in the production of the headlamp, since fewer cables must be assembled by hand. Instead of as before according to the According to the prior art, all light sources in the headlight are to be supplied with energy by means of a plug plugged onto the lamp socket and provided with a connection cable. In the case of the headlamp according to the invention, it is sufficient to provide existing electrical supply contacts of the lamp

To connect headlamps to the vehicle electrical system voltage to power the integrated gas discharge lamp 5 with energy. The supply of existing lamps in the headlamps through the supply contacts of the headlamp is given by a fixed wiring in the headlamp. As a result, the wiring of the headlamp 3 and the integrated gas discharge lamp 5 is considerably simplified.

Another variant of the mechanical adjustment shows the first embodiment of the lamp in Figs. 1 & 2. Here, the studs 703 are arranged on the gas discharge lamp burner 50 side facing the reference ring 702. In this variant, the knobs 703 come to lie on corresponding mating surfaces on the back of the reflector, thereby defining the position of the integrated gas discharge lamp 5 with respect to the reflector 33. The integrated gas discharge lamp 5 is pressed from behind against the reference surfaces of the reflector 33. However, this variant has the disadvantage that the position between the optically effective reflector inside and the reference surfaces on the back of the reflector must be tolerated very accurately in order to achieve a precise optical imaging.

The system of the headlight interface of the second embodiment is also suitable for realizing a further simplified wiring in modern bus systems. Sieren. Thus, the integrated gas discharge lamp 5 next to the two electrical contacts 210, 220 further contacts 230, 240, via which a communication with the on-board electronics of the motor vehicle. The connection element 35 has two slots 351, 352 with correspondingly 2 mating contacts each. In a further embodiment, not shown, only three electrical contacts on the lamp are present, two are essentially used to supply the electrical lamp power, and a logic input, also referred to as a remote enable pin, with the help of the lamp by the on-board electronics of the motor vehicle can be switched on and off almost without power.

This "Snap Lite" interface has in addition to the advantage that a swap of electrical connections is excluded yet another advantage: the fact that the lamp is only supplied with power when it is in its intended place in the headlight, the can The power supply 57 of the gas discharge lamp burner 50, which faces away from the base, is only touched when the integrated gas discharge lamp 5 is safely out of operation the end customer will be able to replace such a lamp, making the integrated gas discharge lamp 5 more cost-effective for the end customer, as there is no need to visit a workshop to replace a lamp. By inserting the integrated gas discharge lamp 5 in the reflector 33, the ground connection of the lamp is also realized with the spotlight housing. This can be achieved, for example, by means of spring strip fastened to the reflector 33 and connected to the ground potential of the vehicle. When inserting the lamp into the headlamp, the spring strips contact the electrically conductive housing surface of the integrated gas discharge lamp 5 and establish an electrical connection between the vehicle mass and the internal ground or the ground shield of the integrated gas discharge lamp. This contacting can take place, for example, on the side wall or on the front side of the housing 72. In the present case, the ground connection by means of the sealing ring 71, which is conductive. Is the

Housing surface is not or not completely electrically conductive, the contacting of the spring steel strip takes place at a contact surface on the housing surface of the integrated gas discharge lamp. This contact surface or these contact surfaces have an electrically conductive

Connection to the internal ground or the ground shield of the integrated gas discharge lamp.

FIG. 31 shows a further fifth embodiment with a conventional interface to the headlight. Here, the integrated gas discharge lamp 5 with the reference surface 702 is pressed by means of a retaining clip 705 onto a corresponding mating surface of the headlight receptacle. The integrated gas discharge lamp 5 is electrically connected to the headlight in a conventional manner. The mounting bracket 705 ensures that the integrated gas discharge lamp 5 with its reference surface 702 is well connected to the receptacle in the headlight, and thus a precise alignment of the electrodes is given in the optical system of the headlamp. The electrodes 504 of the gas discharge lamp burner 50 of the integrated gas discharge lamp 5 are adjusted in the manufacturing process of the integrated gas discharge lamp 5 with respect to the reference surface 702. As a result, the arc of the integrated gas discharge lamp 5 in the reflector assumes a defined position when it is inserted into the headlight, which enables a precise optical imaging. Due to the spring action of the retaining clip 705, this image is ensured even under difficult conditions, such as vibrations, which can occur in an automobile headlight. The retaining clip, in turn, is hooked on the headlight side in a groove 7051, which holds it securely, from which it can nevertheless be easily unhooked when the lamp is replaced. On the bottom side, the retaining clip 705 engages with two bulges 7053 in the base plate 74 a. But it is also conceivable that the retaining clip 705 has no bulges and therefore rests on the ribs of the base plate. With the fifth embodiment of the gas discharge lamp 5 according to the invention, a simple and cost-effective connection to a headlight can be realized, which has no restrictions with respect to the positioning accuracy in the optical system of the headlight.

ignition transformer

The construction of the ignition transformer 80 of the integrated gas discharge lamp 5 will now be explained below. 10 shows a perspective view of the ignition transformer 80 in a first embodiment in which the Ignition transformer 80 has a square flat shape. However, other embodiments are conceivable in which the ignition transformer 80 may have a round, hexagonal, octagonal or other suitable shape. Other embodiments will be described below. In this case, the shape is understood to be the shape of the base area of the essentially prismatic outer dimensions of the ignition transformer, the curves at the body edges being neglected. In the particularly advantageous embodiment shown here, the prism has a small height, in particular a height which is smaller than 1/3 of the diagonal or the diameter of the geometry forming the base surface.

The ignition transformer 80 has a ferrite core 81 composed of a first ferrite core half 811 and an identical second ferrite core half 812. The ignition transformer 80 has on the sides of a plurality of outwardly facing tabs 868, 869, which serve the mechanical attachment of the ignition transformer 80.

Fig. 11 shows a perspective view of the upper

Part of the ignition transformer in which the primary winding and the second ferrite core half 812 are not visible. The first ferrite core half 811 is made up of a square side wall 8112, from which half a hollow cylinder 8110 protrudes centrally inwards. The inside of the square side wall 8112 has outward-inwardly extending elongated recesses 81121 on the winding-facing side. Through these depressions, a impregnating lacquer or a potting compound into which or the ignition transformer 80 is introduced after completion for high-voltage insulation of penetrate outside into the ignition transformer 80 to evenly wet all turns of the ignition transformer 80.

At the outer edge between the two ferrite core halves 811, 812 sits a primary winding 86, which consists of a formed from sheet metal stamped and bent part. The sheet is preferably made of a non-ferrous metal such as copper, bronze or brass. The sheet is preferably elastically deformable and resilient. The primary winding 86 is essentially a long band extending externally between both ferrite core halves 811 and 812. The primary winding 86 is in a first variant with only one turn over 3 corners of the ignition transformer 80, the fourth corner is open. The sheet metal strip of the primary winding 86 is thus wrapped around a three-quarters turn around the outer contour of the ignition transformer and ends in each case a small piece in front of the fourth corner. The sheet metal strip of the primary winding 86 has the above-mentioned tabs 866, 867, 868 and 869, which are mounted in the lateral direction of the sheet metal strip. The four tabs are used for mechanical attachment of the ignition transformer 80, this can be soldered to a board of the ignition electronics 910 as a flat SMD tab or Lötfahne. But the tabs can also have a further 90 ° bend, the tabs are then inserted through the board of the ignition electronics 910, and on the other side verclincht, twisted or soldered, as shown in Fig. 12. The two ends of the sheet metal strip of the primary winding 86 are bent with a radius of about 180 ° to the outside, so that the ends again point away from the fourth corner. In Fig. 12 are the two ends bent by about 90 ° to the outside and the radii with 8620 or 8640 marked. At the outer end of the sheet metal strip each a laterally projecting tab 862, 864 is mounted, which serves the electrical contact. In Fig. 12, an alternative embodiment of the two tabs 862, 864 is shown. The soft connection by means of the 180 ° radius of the two radii 8620 and 8640 voltages in the connection between the primary winding and the circuit board, which can be caused by temperature fluctuations, collected. The tabs are preferably soldered onto the circuit board of the ignition electronics 910 like an SMD component. Due to the above-described 180 ° bending of the sheet metal strip, the soldering point is not loaded with the described mechanical stresses, and the risk of breakage and fatigue of the solder joint is greatly reduced. The alternative embodiment of the tabs 862, 864 has a further 270 ° radius in the tab itself which further reduces the mechanical stresses in the assembled condition.

In the center of the hollow cylindrical inner part of the ferrite core, a contact body 85 is introduced, which establishes the electrical contact between the gas discharge lamp burner 50 and the inner end of the secondary winding 87 (not shown). The contact body 85 consists of a bent sheet-metal part, which is connected to the socket-near power supply 56 of the gas discharge lamp burner 50. The contact body 85 has at its burner remote end two roof surfaces for contacting the high-pressure discharge lamp electrode. Preferably, the contact body 85 at two opposite sides of the burner distal end, two roof surfaces 851 and 852, which are tilted saddle-roof-shaped against each other, and at the ends where the two roof surfaces touch are formed so that a power supply wire 56 of the high-pressure gas discharge lamp burner 50 is clamped centered. For this purpose, the two roof surfaces 851 and 852 are provided with a V-shaped contour at the ends, at which the two roof surfaces 851, 852 touch. However, the contour can also be round or worked out in another suitable way. For mounting the

Power supply wire 56 inserted through the contact body 85 through, cut to a predetermined supernatant, and then preferably welded by laser to the contact body 85.

Fig. 12 shows a perspective view of the lower part of the ignition transformer. The figure shows, inter alia, the second ferrite core half 812, which is shaped identically to the first ferrite core half 811. Also, it is made up of a square side wall 8122, protruding from the middle to the inside half a cylinder 8120. The inside of the square side wall 8122 has outwardly inwardly extending elongated recesses 81221. In the figure, the burner near side of the contact body 85, with its hexagonal open shape, and the passing power supply wire 56 is visible. If the two halves are assembled, a hollow cylinder is formed inside, into which the contact body is inserted. The ferrite core 81 has the shape of a tape or film spool after assembly, except that the outer contour is not round, but square with rounded corners. At the first corner, the ignition transformer has a first return ferrite 814. The second and third corners are also provided with a second return ferrite 815 and third return ferrite 816. The three return ferrites are held by the primary winding 86. For this purpose, the sheet metal strip of the primary winding 86 at the three corners cylindrical, inwardly facing curves 861, 863 and 865, in which the return ferrite 814-816 are clamped. The spring elastically deformable material keeps the three 814-816 return ferrite securely in place during production. The return ferrites represent the magnetic return of the ignition transformer 80, by which the magnetic field lines are held in the magnetic material, and thus no disturbances outside of the magnet

Ignition transformer can cause. This also increases the efficiency of the ignition transformer, in particular the amount of achievable ignition significantly.

13 shows a perspective view of the lower part of ignition transformer 80 with visible secondary winding 87, as it is inserted into second ferrite core half 812 of ignition transformer 80. The secondary winding 87 is made of an insulated metal strip which is wound on the film coil ferrite core like a film having a predetermined number of turns, the high voltage leading end being inside, passed through the center core of the ferrule core and electrically connected to the contact body 85 , The insulation can be applied on all sides to the metal strip, but it can also consist of an insulating film, which with the Metal band is wound up together. The insulating film is preferably wider than the metal strip in order to ensure a sufficient isolation distance. The metal foil is wound with the insulating film so that it comes to rest in the middle of the insulating film. This results in the winding body, a spiral gap, which is filled after impregnation or potting with the impregnating lacquer or the potting compound and thus causes an excellent insulation of the secondary winding 87.

The secondary winding 87 is connected at its inner high-voltage-carrying end 871 with the contact body 85. The outer low-voltage-carrying end 872 of the secondary winding 87 is connected to the primary winding 86. The connections can be made by soldering, welding or other suitable connection method. In the present embodiment, the joints are laser welded. For this purpose, preferably two welding points are applied per end, which connect the two parts safely and electrically conductive with each other. The inner end 871 of the secondary winding 87 passes through the two hollow cylinder halves 8110, 8120 of the ferrite core 81, and is clamped by them. The outer end 872 of the secondary winding 87 is connected to the end of the primary winding 86, that the Wickelsinn the

Secondary winding 87 is directed against the winding sense of the primary winding 86 opposite. Depending on the requirement, however, the outer end of the secondary winding 87 can also be connected to the other end of the primary winding 86, so that the winding sense of the primary and the secondary winding is the same. Hereinafter, the diameter and the height of the ignition transformer 80 which is housed in the integrated gas discharge lamp 5, largely independent of its geometry and based on the dimensions of the ferrite core to be defined, for a simpler description distinguished. The height of the ignition transformer is understood to mean the distance between the two outer surfaces of the two side walls which are remote from the winding, which corresponds approximately to the sum of twice the thickness of a side wall and the width of the winding. Below the diameter of the ignition transformer 80 is understood below regardless of the shape of the side walls, the longest distance within one of the two side walls, wherein the Stecke lies within any plane, said plane being parallel to the outer surface of the respective side wall.

In a particularly advantageous embodiment, the ferrite core of the ignition transformer has a height of 8 mm and a diameter of 26 mm. The side walls have a diameter of 26 mm and a thickness of 2 mm and the center core a diameter of 11.5 mm with a height of 6 mm. The secondary winding consists of 42 turns of a Kapton film 5.5 mm wide and 55 microns thick on a centered in the longitudinal direction 4 mm wide and 35 microns thick copper layer is applied. In a further particularly advantageous embodiment, the secondary winding is wound from two separate, superimposed films, wherein a 75 micron thick copper foil and a 50 micron thick Kapton foil is used. In both embodiments, the secondary winding is electrically conductive with the one turn comprehensive primary winding connected, wherein the primary winding is driven by a pulse generating unit comprising a 800 V spark gap.

14 shows an exploded view of the ignition transformer 80 in a second embodiment. Since the second embodiment is similar to the first embodiment of the ignition transformer 80, only the differences from the first embodiment will be described below. The ignition transformer 80 in the second embodiment has a round shape, similar to a film coil. The round shape eliminates the return ferrite 814-816, and the primary winding 86 has a simpler shape. The laterally extending tabs for the mechanical attachment of the transformer are here designed as SMD tabs, which have a 270 ° bend to protect the solder joints from excessive mechanical stresses. The two tabs 862, 864 for electrical contacting are designed in the same way and arranged radially on the circumference of the ignition transformer 80. The ferrite core 82 of the second embodiment is formed in three parts, it has a hollow cylindrical center core 821, which is completed at its two ends by round plates 822. The circular plates 822 come to lie centrally on the hollow cylinder 821, thus resulting in the above-described film coil form.

The hollow cylinder has a slot 823 (not visible in the figure) in order to be able to pass the inner end of the secondary winding 87 into the interior of the hollow cylinder.

15 shows a sectional view of the second embodiment of the ignition transformer 80. Here, the structure of the ferrite core 81 is easy to understand. In this see also the slot 823 can be seen, through which the inner end of the secondary winding 87 is passed.

16 shows an exploded view of the ignition transformer in a third round embodiment with a two-turn primary winding. Since the third embodiment is very similar to the second embodiment of the ignition transformer 80, only the differences from the second embodiment will be described below. In the third embodiment, the ignition transformer 80 has a primary winding with two turns. The metal strip of the primary winding 86 thus passes almost twice around the ignition transformer. At the two ends in turn tabs for electrical contacting of the ignition transformer 80 are mounted, which are designed as an SMD variant. The tabs for mechanical attachment of the ignition transformer 80 are missing in this embodiment, the ignition transformer 80 must therefore be otherwise mechanically fixed. This can be accomplished, for example, by pinching the ignition transformer 80, as indicated in FIG. 3. The ignition transformer 80 is clamped here between the base 70 and the base plate 74. The base plate 74 has for this purpose a base plate dome 741, an increase on the base plate, which clamps the ignition transformer 80 in the installed state. The advantage of this design is the good heat dissipation of the ignition transformer 80. This can be very hot during operation because it sits very close to the gas discharge lamp burner 50 of the integrated gas discharge lamp 5. Due to the thermally highly conductive base plate 74, a part of the heat that is introduced from the gas discharge lamp burner 50 into the ignition transformer 80, be discharged again and the ignition transformer 80 are effectively cooled.

17 shows a sectional view of the ignition transformer 80 in a third round embodiment with a two-winding primary winding. Again, this sectional view shows very well the core structure of the ferrite core 82. The ferrite core 82 is composed of three parts, as in the second embodiment, a center core 824 and two plates 825, 826. The center core 824 is also hollow cylindrical and has one end a shoulder 827 which engages a round cutout of the first plate 825 and fixes it on the center core 824. A second plate 826 also has a round cutout whose inner radius corresponds to the outer radius of the center core 824. This plate is attached after mounting the secondary and the primary winding on the center core and thereby fixed. The plate is plugged in until it comes to rest on the secondary winding in order to achieve the best possible magnetic flux in the ignition transformer 80.

Asymmetrical ignition pulse

The operation of the ignitor of the integrated gas discharge lamp 5 will be explained below.

FIG. 18 a shows the schematic circuit diagram of an asymmetrical pulse ignition device according to the prior art. In the case of the asymmetrical ignitor, the ignition transformer T _{IP is connected} to one of the supply lines of the gas discharge lamp burner 50, which is shown here as an equivalent circuit diagram. This results in a firing pulse, which depends on the ground reference potential, which is usually with the other Zulei- tion of the gas discharge lamp burner, generates only in one 'direction' a voltage; In other words, either a voltage pulse which is positive with respect to the ground reference potential or a voltage pulse which is negative with respect to the ground reference potential is generated. The operation of an unbalanced pulse ignition device is well known and will not be explained further here. The unbalanced voltage is well suited for single-ended lamps, as the ignition voltage is applied only to one of the two gas discharge lamp burner electrodes.

For this purpose, the pedestal near electrode is chosen regularly, since it is not touchable and thus in case of improper use is no hazard to humans. At the normally open guided return conductor is not dangerous for humans voltage, thus ensuring a powered with a single-ended ignitor lamp ensures a certain security. However, the asymmetrical ignitor has the disadvantage of applying the complete ignition voltage to a gas discharge lamp electrode. This increases the losses due to corona discharges and other effects caused by the high voltage. This means that only part of the generated ignition voltage is actually applied to the gas discharge lamp burner 50. Thus, a higher ignition voltage must be generated than necessary, which is complicated and expensive.

Fig. 18b shows the schematic diagram of a symmetrical Impulszündgerätes according to the prior art. The symmetrical pulse ignition device has an ignition transformer T _IP , which has two secondary windings, which are magnetically coupled together with the primary winding are. The two secondary windings are oriented so that the generated voltage of both secondary windings adds to the lamp. Thus, the voltage is distributed in about half of the two gas discharge lamp electrodes.

As mentioned above, the losses are reduced by corona discharges and other parasitic effects. The cause of the i. A. Higher ignition voltage in the case of symmetrical pulse ignition is only apparent after a closer look at the parasitic capacitances. For this purpose, the lamp equivalent circuit diagram of the gas discharge lamp burner 50 is considered in FIG. 18b. A large, if not the largest portion of the parasitic lamp capacitance C _La is not caused by the lamp itself, but by the connection between the lamp and the ignition unit, for example by the lamp lines. However, these not only have parasitic capacitances from conductor to conductor, but also between conductor and environment. Assuming a simplification of a description with concentrated energy storage, the parasitic capacitances between the two conductors and the two gas discharge lamp electrode to C _La , 2 summarize, as shown in Fig. 18b. The respective parasitic capacitances present between the conductor and the environment are modeled by C _La , i and C _La , ₃ , respectively. In the following, the potential of the environment, for example of the housing, is regarded as spatially constant and represented by the grounding symbol, even if this does not have to match the PE or PEN in the sense of a low-voltage network. In addition, it should be assumed that a symmetrical structure and thus of C _La , i = C _La , 3. The parasitic Lamp capacity results according to the extended equivalent circuit diagram C _La , 2 + 1/2 C _La , i-

The difference between the unbalanced pulse ignition and the symmetrical pulse ignition is clear, taking into account that the converter and the ignition unit also have parasitic capacitances with respect to the environment. These are in part intentionally increased (eg, line filters) and are generally much larger than the parasitic capacitances of the lamp as viewed above with respect to the environment, and therefore, for simplicity, consideration can be given to ignition from ambient potential electronics. Neglecting the voltage UW, in the case of the asymmetrical ignition C _La , i and C _La , 2 are therefore charged to the ignition voltage, whereas in the case of the symmetrical ignition C _La , 2 to the ignition voltage and C _La , i and C _La , 3 respectively are to be charged half the ignition voltage. Assuming a symmetrical structure, ie C _La , i = C _La , 3, less energy is required for the charging of the parasitic capacitances in the symmetric pulse ignition than for the asymmetrical variant. In the extreme case C _La , i = C _La , 3 >> C _La , 2, the ignition unit according to Fig. 18a, compared with that of Fig. 18b, to provide almost twice the energy.

Another advantage of the symmetrical ignition is the lower required insulation resistance to the environment, since the occurring voltages Ui _so i, i and Ui _so i, 2 have only half the value compared to the voltage Ui _so i in the case of asymmetrical ignition. This also shows the disadvantage of symmetrical impulse ignition and the reason why they are often not In the case of symmetrical ignition, both lamp terminals carry high voltage, which is often inadmissible for safety reasons, since in many lamp or base constructions one of the two lamp terminals, usually the lamp remote, which is then referred to as "lamp back", touched can be .

This shows that the symmetrical ignition method is optimally suited for double-ended gas discharge lamps, which are designed to be symmetrical in terms of mechanical design. In a single ended gas discharge lamp, as previously mentioned, there is the problem of ignition voltage applied to the open user-reachable gas discharge lamp electrode. Another problem is the voltage applied to the remote base gas discharge lamp electrode voltage with respect to the potential of the reflector. The reflector in which the gas discharge lamp is installed is usually grounded. Thus, a high voltage between the return conductor of the base remote electrode and the reflector is in the ignition. This can lead to flashovers on the reflector, resulting in malfunction. For these reasons, symmetrical ignition is unsuitable for single capped gas discharge lamps.

In addition, it should be noted that the insulation effort increases non-linearly with the voltage to be isolated. Due to non-linear effects in insulating materials, when the voltage is doubled, the distance between two conductors typically has to be doubled more in order to avoid flashover. In addition to the above-considered, purely capacitive behavior of the environment or the insulating materials involved, can, from a certain voltage or the resulting field strengths in the insulating materials and at their Grenzflä- chen, a real power conversion in the insulating materials eg by corona discharges, partial discharges, etc. no longer be neglected. In the above equivalent circuit diagrams, additional non-linear resistors are to be added parallel to the capacitances. From this point of view, too, the symmetrical pulse ignition is preferable to the unbalanced one.

Finally, the observation should be made that, after a certain stress load of the insulating material, it ages considerably faster and, in the case of a slight reduction in stress, a significantly longer service life can therefore already be expected.

A good compromise, which combines the advantages of both ignition methods in itself, is the asymmetric pulse ignition, as can be seen in Fig. 19 in a schematic representation. It has a similar structure as a symmetrical ignition, but the two secondary windings have different numbers of turns. The disadvantage of the symmetrical ignition method is, above all, that an accidental contact with the return conductor during ignition and thus the contact of a high-voltage-carrying metal part by the user can not be excluded. In the case of the integrated gas discharge lamp 5, which has the above-described headlight interface according to FIG. 5, this can be ruled out since the power supply of the electronics does not take place until it has been inserted into the headlight. Thus, it is impossible to touch the return conductor of the remote base electrode with intact headlight when it leads to voltage. As already mentioned above, a symmetrical ignition is not possible here as well, since surges on the usually grounded reflector must be feared. It is therefore proposed an asymmetric ignition, for example, Η the ignition voltage on the base near the electrode, and eg ¹ ^ the ignition voltage to the base remote electrode. The exact voltage ratio between the electrodes of the gas discharge lamp burner 50, that is, the socket near the first lamp electrode and the socket remote second lamp electrode depends on many factors, the lamp size and the base construction. The voltage ratio between the sockelahen first lamp electrode and the sockelfernen second lamp electrode can range from 22: 1 to 5: 4. On the return conductor secondary winding of the ignition transformer T IPSR _ΣP voltages from 2..8 kV are preferably generated, and the Hinleiter- secondary winding of the ignition transformer T IPSH _ΣP voltages of 23..17 kV are preferably generated. This results in preferred transmission ratios between the two secondary windings not equal to 1, namely ni _PSR : ni _PSH = 2:23 ... 8:17. This can also be expressed as the equation n _IPSR = 0, 04..0, 8 * n _IPSH . Thus, the structure is similar to that of a symmetrical igniter, but the secondary windings are not evenly distributed.

The number of primary windings n _{p of} the ignition transformer T _ΣP is preferably between 1 and 4, the sum of the number of turns of both secondary windings IPSH and IPSR is preferably between 40 and 380. The pulse ignition unit Z in FIG. 19 is well known from the prior art and will therefore not be explained in detail here. It consists of at least one capacitor, which is connected via a switching element to the primary winding of the ignition transformer. In this case, a switching element with a nominal tripping voltage between 350V and 1300V is preferably used. This can be a switching spark gap or a thyristor with a corresponding drive circuit. In the present first embodiment, the ignition transformer T _{IP has} a transmission ratio ni _PP : nip _SR : ni _PSH of 1: 50: 150 turns, with an ignition unit Z based on a 400 V spark gap, ie with a nominal spark gap Trigger voltage of 400 V, is operated. The ignition transformer T _ΣP supplies a peak voltage of +5 kV to earth at the non-pedestal electrode of the gas discharge lamp burner 50 and a peak voltage of -15 kV to ground at the base near the electrode of the gas discharge lamp burner 50.

In a further second embodiment, the ignition transformer is implemented with a gear ratio of 3: 50: 100 turns, and is operated with an ignition unit Z based on an 800 V spark gap. This supplies a peak voltage of -8 kV to earth at the base-remote electrode of the gas-discharge lamp burner 50 and a peak voltage of +16 kV to ground at the base-near electrode of the gas-discharge lamp burner 50.

FIG. 20 shows the schematic circuit diagram of an extended circuit of the integrated gas discharge lamp 5. Here, one or two non-saturating inductors L _NS i and L _NS 2 are shown each switched between the high-voltage end of each of a secondary winding and the respective Brenneran- circuit to prevent glitches with high voltage spikes (so-called glitches). Inductance values of 0.5uH to 25uH, preferably of 1uH to 8uH are used. In addition, a high-voltage-resistant capacitor C _B (a so-called "burner capacitor") can be connected directly in parallel with the gas discharge lamp burner and thus between the gas discharge lamp burner and the non-saturating reactor.

This usually has a capacity of less than 22pF in order not to steam the ignition pulse too much. Preferably, it has a capacity between 3pF and 15pF. The capacitor can be structurally realized by a corresponding arrangement and design of the encapsulated Lampenstromzu- guides, for example in the form of plates. The capacitor has two positive influences: on the one hand, it is advantageous for the EMC behavior of the lamp since high-frequency disturbances which are generated by the lamp are short-circuited directly at the place of formation, on the other hand it ensures a lower-resistance breakthrough of the burner, which facilitates in particular a takeover by the operating circuit 20.

By means of a conclusion capacitor C _RS , with a capacitance value which is preferably between 68pF and 22nF, for the very fast pulses generated by the ignition transformer T _ΣP a termination of the pulse igniter is achieved with respect to the ECG, which has a very low impedance. As a result, the generated high-voltage ignition pulses are fully absorbed in a very good approximation

Burner on. The inference capacitor C _RS forms together men with a return conductor choke L _R a low pass. This counteracts electromagnetic interference and protects the ECG output from excessive voltages. The extended circuit also has a current-compensated inductor L _S κ, which also counteracts electromagnetic interference. A suppressor diode D _Tr , also called a clamping diode, limits the voltage generated at the operating circuit 20 due to the ignition process and thus protects the output of the operating circuit 20.

The gas discharge lamp burner 50 of the integrated gas discharge lamp 5 is fastened to the base 70 by means of a metal clip 52 and four retaining plates 53 (see, for example, FIG. 1). As already indicated in FIG. 20, this metal clip 52 is now grounded, ie, laid in an integrated gas discharge lamp for automobiles, for example, on body ground. The earthing of the metal clamp reliably prevents a flashover from the metal clamp to the headlight, since both parts are at the same potential during ignition. Furthermore, the earthing of the metal clip produces a particularly good capacitive coupling to an ignition auxiliary coating located on the gas discharge lamp burner vessel. Such primer coatings are often applied to high pressure discharge lamp burners to reduce the high ignition voltages. This measure increases the ignition voltage lowering property of the ignition assist coating located on the gas discharge lamp burner vessel. It is particularly advantageous if the capacitive influence of the metal clip on the gas discharge lamp burner (possibly including its Zündhilfsbe- coating) is increased. For this purpose, more electric conductive parts galvanically or capacitively coupled to the metal bracket. This results in a kind of "third electrode", which consists of several "coupled together individual electrodes" and is grounded on one side. For example, this third electrode in addition to the

Metal clip additionally comprise a metallic coating 54 on the outer bulb, as indicated in Fig. 21. The coating can be applied to the outside and / or on the inside of the outer bulb. The coating consists of electrically conductive, for example, metallic material and is preferably mounted in a strip parallel to the return conductor. As a result, the metallic coating 54 does not appear optically and, moreover, there is a minimum distance and thus a maximum coupling capacity for the auxiliary ignition coating on the burner vessel. The coating on the outer bulb may be capacitively or galvanically coupled to the metal clip. For a galvanic coupling, it is particularly advantageous if the electrical contacting of the outer coating with the metal clip takes place by fixing the burner in the metal clip, which can be realized without additional overhead by a common assembly technique according to the prior art. The coating preferably extends over 1% to 20% of the outer envelope circumference.

The positive effect of the grounded metal clamp on the ignition voltage of a gas discharge lamp is due to the following physical context: the fact that with a grounded metal clamp and an asymmetric pulse ignition between the metal clamp and both Gas discharge lamp electrodes is applied a high voltage, a dielectrically impeded discharge in the outer bulb is favored in the vicinity of both gas discharge lamp electrodes. The dielectrically impeded discharge in the outer bulb favors a breakdown in the burner vessel. This is promoted by the UV light, which arises in the dielectrically impeded discharge and is hardly absorbed by the burner vessel, and favors the generation of free charge carriers at the electrodes and in the discharge space and thus reduces the ignition voltage.

The metal bracket and the reference plane to the reflector of the integrated gas discharge lamp 5 may consist of a metal part, which has corresponding armature, which are encapsulated by plastic and ensure a good mechanical connection to the base 70. The grounding of the metal clip is then carried out automatically by inserting the lamp in the reflector respectively in the headlight. This makes the reference plane now more robust against mechanical wear, which is advantageous due to the increased weight of an integrated gas discharge lamp 5. The training according to the prior art provides only a plastic injection molded part as a reference plane.

In a preferred embodiment of the integrated gas discharge lamp 5, the base consists of 2 parts. A first part with an already adjusted gas discharge lamp burner 50, which is embedded by means of the metal bracket 52, and the retaining plates 53 in a base made of plastic, which has a metal-reinforced reference plane as described above. This first part is with connected to a second part, which contains the ignition and operating electronics. The connections for the lamp as well as the power supply lines can be accomplished by welding, soldering, or by a mechanical connection such as a plug contact or an insulation displacement contact.

Fig. 21 shows a gas discharge lamp burner 50 which will be described below. The gas discharge lamp burner 50 is preferably a mercury-free gas discharge lamp burner, however, a mercury-containing gas discharge lamp burner may also be used. The gas discharge lamp burner 50 accommodates a gas-tight discharge vessel 502 in which electrodes 504 and an ionizable filling are enclosed for generating a gas discharge, wherein the ionizable filling is preferably formed as a mercury-free filling comprising xenon and halides of the metals sodium, scandium, zinc and indium , and the weight ratio of the halides of zinc and indium in the range of 20 to 100, preferably 50, and wherein the

Cold pressure of the xenon gas is in the range of 1.3 megapascals to 1.8 megapascals. It has been found that thereby the decrease of the luminous flux with the operating time of the gas discharge lamp burner 50 and the increase of the burning voltage of the gas discharge lamp burner 50 can be reduced with its service life. That is, the gas discharge lamp burner 50 has improved luminous flux maintenance compared with a prior art gas discharge lamp burner and exhibits a longer life due to the lower increase of the operating voltage over the operating life. Except- the gas discharge lamp burner 50 shows over its service life only a small shift of the color location of the light emitted by it. In particular, the color locus migrates only within the limits allowed by ECE Rule 99. Both the comparatively high cold pressure of the xenon and the comparatively high proportion by weight of the halides of the zinc contribute significantly to the setting of the burning voltage of the gas discharge lamp burner 50, that is to say the voltage which occurs after the ignition phase has ended in the quasi-stationary operating state over the discharge path of the gas discharge lamp burner 50. at. The halides of indium are present in such a small proportion by weight that they contribute to adjusting the color locus of the light emitted by the gas discharge lamp burner, but do not make a significant contribution to adjusting the burning voltage of the gas discharge lamp burner 50. The halides of indium in the gas discharge lamp burner 50, as well as the halides of sodium and scandium, mainly serve the light emission.

Advantageously, the weight fraction of halides of zinc ranges from 0.88 micrograms to 2.67 micrograms per 1 mm ³ discharge vessel volume and the weight percent of indium halides ranges from 0.026 micrograms to 0.089 micrograms per 1 mm discharge vessel volume. As halides, iodides, bromides or chlorides can be used.

The proportion by weight of the halides of sodium is advantageously in the range of 6.6 micrograms to 13.3 micrograms per 1 mm ^{3 of} the discharge vessel volume and Weight fraction of halides of scandium in the range of 4.4 micrograms to 11.1 micrograms per 1 mm ^{3 of} the discharge vessel volume to ensure that the gas discharge lamp burner 50 produces white light with a color temperature of about 4000 Kelvin and the color locus during the Life of the gas discharge lamp burner 50 in the white light range, preferably remains within narrow limits. At a lower weight fraction, the losses of sodium (due to diffusion through the vessel wall of the discharge vessel) and scandium (due to chemical reaction with the quartz glass of the discharge vessel) can no longer be compensated, and at a higher weight fraction, the color location and the color temperature are changed.

The volume of the discharge vessel is advantageously less than 23 mm ³ in order to come as close as possible to the ideal of a point light source. For use as a light source in a vehicle headlight or other optical system, the light emitting part of the discharge vessel 502, that is, the discharge space with the electrodes enclosed therein, should have the smallest possible dimensions. Ideally, the light source should be punctiform in order to position it at the focal point of an optical imaging system. The inventive high-pressure discharge lamp 5 comes closer to this ideal than a high-pressure discharge lamp according to the prior art, since it preferably has a discharge vessel 502 with a smaller volume. The volume of the discharge vessel 502 of the high-pressure discharge lamp 5 is therefore advantageously in the range of greater than or equal to 10 mm to less than 26 mm. The distance between the electrodes 504 of the gas discharge lamp burner is preferably less than 5 millimeters in order to come as close as possible to the ideal of a point light source. For use as a light source in a motor vehicle headlight, the electrode spacing is preferably 3.5 millimeters. As a result, the gas discharge lamp burner 50 is optimally adapted to the imaging conditions in the vehicle headlight.

The thickness or the diameter of the electrodes 502 of the gas discharge lamp burner is advantageously in the range of 0.20 millimeters to 0.36 millimeters. Electrodes with a thickness in this range of values can still be embedded sufficiently reliably in the quartz glass of the discharge vessel and at the same time have sufficient current-carrying capacity, which is particularly important during the so-called start-up phase of the high-pressure discharge lamp, during which they have 3 to 5 times their rated power and rated current is operated. In the case of thinner electrodes in the present embodiment with mercury-free filling no sufficient current carrying capacity would be guaranteed and in the case of thicker electrodes 504 there would be a risk of cracking in the discharge vessel, due to the occurrence of mechanical stresses due to the significantly different thermal expansion coefficients from the discharge vessel material, which is quartz glass, and the electrode material, which is tungsten or tungsten doped with thorium or thoria. The electrodes are in each case connected to a molybdenum foil 506 embedded in the material of the discharge vessel, which enables a gas-tight current feedthrough, and the smallest distance between the respective molybdenum foil 506 and the end of the electrode connected to it in the interior of the discharge vessel 502 is advantageously at least 4.5 mm, in order to ensure the greatest possible distance between the respective molybdenum foil 506 and the on the projecting into the discharge vessel 502 electrode tips gas discharge. This consequent, comparatively large minimum distance between the molybdenum foils 506 and the gas discharge has the advantage that the molybdenum foils 506 are exposed to a lower thermal load and a lower risk of corrosion by the halogens in the halogen compounds of the ionizable filling.

frequency adjustment

In the following, a method for avoiding flicker or flicker phenomena is described, which the

Operating electronics of the integrated gas discharge lamp 5 executes.

The gas discharge lamps considered here must be operated with alternating current, which is generated primarily by the operating electronics 920. This alternating current can be a high-frequency alternating current, in particular with a frequency above the acoustic resonances occurring in gas discharge lamps, which in the case of the lamps considered here corresponds to a frequency of the lamp current above approximately 1 MHz. Usually used However, the low-frequency square-wave operation is considered, which is considered below.

Gas discharge lamps, in particular high-pressure discharge lamps, in the case of incorrect operation, generally tend to break the arc when the lamp current changes direction, the so-called commutation, which is due to a too low temperature of the electrodes. Typically, high pressure discharge lamps are operated with a low frequency square wave current, which is also called "wobbly DC operation." In this case, a substantially rectangular current with a frequency of typically 100 Hz up to a few kHz is applied to the lamp and negative driving voltage, which is essentially provided by the operating electronics, the lamp current commutates, resulting in a momentary zero of the lamp current This operation ensures that the electrodes of the lamp are uniformly loaded despite a quasi-DC operation.

The arc approach, that is, the approach of the arc on the electrode is fundamentally problematic in the operation of a gas discharge lamp with alternating current. During operation with alternating current, the cathode becomes an anode during commutation and, conversely, an anode becomes a cathode. The transition cathode-anode is inherently relatively unproblematic, since the temperature of the electrode has approximately no influence on their anodic operation. In the anode-to-cathode transition, the ability of the electrode to supply a sufficiently high current depends on its temperature. If this is too low, the arc changes during commutation, mostly at least after the zero crossing, from a punctiform arc approach mode to a diffuse arc approach mode. This change is accompanied by an often visible collapse of the light emission, which can be perceived as flickering.

It makes sense that the lamp is thus operated in punctiform Bogenansatzbetriebsweise, since the bow approach here is very small and therefore very hot. As a result, due to the higher temperature at the small starting point, less voltage is required in order to be able to supply sufficient current.

In the following, commutation is considered to be the process in which the polarity of the driving voltage of the gas-discharge lamp burner 50 changes, and therefore, a large current or voltage change occurs. In a substantially symmetrical operation of the lamp is at the middle of the commutation of the voltage or current zero crossing. It should be noted that the voltage commutation usually always runs faster than the current commutation.

Aus, The boundary layers of ac-arcs at HID-electrodes: phase resolved electrical measurements and optical observations', O. Langenscheidt et al. , J. Phys D 40 (2007), pp. 415-431, it is known that with a cold electrode and a diffuse arc approach, the voltage after commutation initially increases, since the too cold electrode can supply the required current only by a higher voltage. If the device for operating the gas discharge lamp can not supply this voltage, then the above-mentioned flickering occurs. The problem of the changing bow approach mode relates above all to gas discharge lamps, which have comparatively large electrodes compared to similar lamps of the same nominal power. Typically, lights are then overloaded when "instant light" is required, such as xenon discharge lamps in the automotive sector, where 80% of the light output must be reached after 4 seconds due to regulatory requirements. Quickstarts, also referred to as start-up phase, operated at significantly higher power than their rated power to meet the applicable automotive standards or regulations. Therefore, the electrode is dimensioned for the high starting power, but is too large in relation to the normal operating condition. Now, since the electrode is heated mainly by the lamp current flowing therethrough, the problem of flicker occurs especially in aged gas discharge lamps whose burning voltage is increased at the end of the life. Due to the increased burning voltage flows a smaller lamp current, as the

Operating electronics while stationary lamp operation keeps the lamp power constant by means of regulation, which is why the electrodes of the gas discharge lamp are not sufficiently heated at the end of life.

In an integrated gas discharge lamp, there is now an advantage in that the operating electronics are inseparably connected to the gas discharge lamp burner, so that the previous burning time, also referred to as cumulative burning time t _k , which was operated by summation of all periods in which the gas discharge lamp burner, regardless of the between them lying periods in which the gas discharge lamp burner was not operated, results, can be detected by the operating electronics in a simple manner. This detection may be done, for example, by a nonvolatile memory timepiece which measures the time each time the gas discharge lamp burner 50 is operated, thus burning an arc between the electrodes. Since the problem of flicker occurs primarily in older lamps, a method is proposed in which the operating frequency with which the gas discharge lamp burner is operated is adapted to the burning time of the gas discharge lamp burner in such a way that the operating frequency is increased with increasing burning time. This offers the following advantages: The change of anodic and cathodic operating phase, which is accompanied by a temperature modulation of the electrode tips, is faster at a higher frequency. Consequently, the higher the frequency, the lower the temperature swing of the electrode tips due to their thermal inertia. Surprisingly, it has been found that at an electrode temperature above a "critical minimum temperature" of the lamp electrodes, there is no flicker.

However, the frequency may not be increased arbitrarily, as otherwise excitation of acoustic resonances in the lamp, which may undergo a deformation of the arc as well as flickering, can occur. This effect is already possible from frequencies of 1 kHz, which is why one usually selects a frequency of 400 Hz or 500 Hz for normal operation, ie after the ignition and start-up phase in the stationary operating phase. This frequency will be referred to below as the lower limit designated frequency. In the following, the term "low cumulative burning time" is regarded as a burning time in which the burner 50 of the gas discharge lamp 5 shows no or only a few aging effects. This is the case until the cumulative burning time reaches approximately the first 10% of the specified life of the gas discharge lamp 5. The term 'near the specified life' is hereafter considered to be a lifetime at which the cumulative burn time slowly reaches the specified life, eg, between 90% and 100% of the specified life. The specified lifetime is considered to be the life specified by the manufacturer.

Fig. 22 shows the diagram of a first embodiment of the method, in which the operating frequency of the gas discharge lamp burner is plotted over its burning time. It is easy to see that the operating frequency remains constant at 400 Hz for a burning time of 500 h, then gradually increased by 0.5 Hz / h to 900 Hz during the firing time of 500 h to 1500 h, and then off to stay at 900 Hz.

The frequency increase in the range 500 h to 1500 h, however, does not have to be continuous, but can also be done in stages. Thus, in a second variant of the first embodiment of the method shown in Fig. 32, from a cumulative burning time of 2097152 s, which corresponds to about 583 h, always after the expiration of 32768 s, which corresponds to about 9, 1 h, the Frequency increased by 4 Hz. The frequency is increased until 128 increments have been made. Then the frequency has - starting from the original start value of 400 Hz - the Value reaches 912 Hz. The second variant of the first embodiment of the method is particularly suitable for implementation by means of digital logic, for example by a microcontroller or a digital circuit in an ASIC, since it requires only discrete time and frequency steps.

In the third variant of the first embodiment, which is shown in FIG. 33, a particularly simple implementation is used. Here, after a time of 1048576 s, which corresponds to about 291 h, the frequency is doubled in one step from 400 Hz to 800 Hz. Subsequently, the lamp is always operated at the high frequency. In contrast to the second variant of the first embodiment, only a single frequency step takes place.

In a second embodiment, shown in FIG. 34, the above method is combined with a flicker detecting circuit (not shown) to enable the frequency to be adapted as needed to the requirements of the lamp torch. The circuit arrangement for detecting flickers is based on a detection circuit which uses the lamp voltage and / or the lamp current for detection. Alternatively, suitable correlating variables can be used before the inverter for detection. An electronic operating or

Ballast as it is usually used in the motor vehicle and may be included as operating electronics 920 in the integrated gas discharge lamp 5, has a two-stage structure consisting of DC voltage converter and inverter via a

DC link are coupled together, wherein the temporal voltage change of the DC intermediate circuit and / or the temporal current change of the current flowing into the inverter from the intermediate circuit can be regarded as a measure of the flickering of the lamp.

The flicker detecting circuit now detects whether flickering occurs at the lamp. If this is the case and the previous burning time of the lamp is greater than 500 h, a Flacker mapping method is set in motion.

The method comprises the following steps:

- Increase the count of a flacker minimum search by one

Stepwise increase of the operating frequency of the gas discharge lamp burner starting from the lower limit frequency,

- Measurement of Flackerintensität at the selected operating frequency.

In each case at least the Flackerintensität is stored at the selected operating frequency. If necessary, further parameters measured at the operating frequency are stored. Flicker intensity must be measured over a comparatively long period of time in order to compensate for statistical fluctuations which may occur during operation. In the second embodiment, for example, a measuring time of 20-30 minutes is provided. The frequency is increased by 100 Hz, and then measured the Flackerintensität. In a first stage, the frequency is increased up to a first upper limit frequency of 900 Hz. As soon as that Flickering disappears or the flicker intensity drops below a permissible threshold value, the increase of the frequency does not continue, the current frequency is saved for future operation in a non-volatile memory, so that at the next

Restarting the integrated lamp is started immediately with the last operated frequency.

If the flicker could not be removed despite an increase up to the first upper limit or the flicker intensity could not be lowered below a permissible threshold value, the counter reading of the Flacker minimum search is increased by one and the frequency is increased further until the triple value the first upper limit frequency, in this case 2700 Hz, the so-called second upper limit frequency is reached. Thereafter, the frequency is selected from the entire measured range between the lower limit frequency and the second upper limit frequency at which the slightest flicker has occurred. The flicker intensity associated with the slightest flickering is multiplied by a factor greater than 1 and the so-called flicker limit is stored as the new permissible threshold value.

In the following, the monitoring and measurement of the flickering remains activated and it is checked periodically whether the current flicker intensity is above the current flicker intensity

Flackergrenze is. If this is the case, jump to the frequency which has shown the second lowest flicker intensities in the previously described examination of the lamp in the context of this method. At this frequency, the lamp is then operated while continuing to monitor and measure the flicker remains activated. If the current flicker intensity is again above the current flicker limit, the frequency with the third lowest Flicker intensity is changed. If, in the subsequent operation, the current flicker intensity is also above the current flicker limit, the count of the flicker minimum search is again increased by one and a new cycle of the minimum search is started, the entire frequency range between the lower limit frequency and the second upper limit frequency is examined.

The count of how often the flicker minimum search has already been activated as well as the current flicker limit are stored in the nonvolatile memory of the operating electronics (920, 930). These two values can be read out via the communication interface of the integrated gas discharge lamp, for example via a LIN bus. As part of the maintenance of the motor vehicle, for example in the context of inspection after expiry of a service interval, or because the motor vehicle is due to a defect in the workshop, the two values are read and compared with limits representing the still tolerated values. The limits can also be stored in the integrated gas discharge lamp and read out via the communication bus, but are stored in the preferred embodiment in the diagnostic device of the workshop for the sake of simplicity. If one of the read-out values is above the corresponding limit value, the integrated gas discharge lamp (5) must be replaced with a new integrated gas discharge lamp. This procedure increases the availability the lighting system significantly, without causing significant costs, since the lamp is not unnecessarily replaced early and during maintenance no significant additional time required, since the vehicle is already connected to the diagnostic device.

The limit values with which the data from the nonvolatile memory of the operating electronics are compared can be changed as a function of the cumulative burning time (t _k ) or the cumulative weighted burning time (t _kg ) likewise read from the nonvolatile memory, such that, for example, the flicker limit of an old one Lamp may be higher than a new lamp without the lamp would have to be replaced. The dependencies of the limit values as a function of the burning time of the lamp are made available to the motor vehicle manufacturer by the lamp manufacturer, so that the latter can enter the data in his diagnostic device, for example in the form of a table or data matrix.

In a third embodiment, the procedure is analogous to the second embodiment, however, in particular in order to save storage space in the microcontroller, in the search described above, only the value of the previously minimal flicker intensity and the associated operating frequency are stored. This means that instead of a real mapping, only a minimum search with respect to flicker intensity is performed. If, during the first search operation, no aborted search has been carried out up to the first upper limit frequency, then, as in the second embodiment, it will also be up to the second upper one

Grenzfrequenz further searched. Subsequently, directly to the frequency stored in the minimum memory is jumped. Subsequently, the lamp is operated for at least 30 minutes at this frequency and during this time determines the Flackerintensität over this period. If this is increased by more than one permissible factor, for example 20% compared to the original one, a new search for the best possible operating frequency is started and proceeded as described above.

By increasing the operating frequency of the gas discharge lamp burner over its burning time, a flicker tendency of the burner can be significantly reduced, without the need for expensive measures on the circuit itself. The fact that the operating electronics of the integrated gas discharge lamp 5 contains a microcontroller, the entire process can be implemented in the software of the microcontroller, and thus causes no additional costs. The circuit arrangement for detecting flickering of the second embodiment can also be implemented purely in software with skillful design. Because the measured quantities necessary for the detection of flickers already rest on the microcontroller for other reasons, a detection unit can be implemented in software by suitable evaluation of these variables. The circuit components required in hardware are already present for other reasons and thus cause no additional costs.

Communication Interface

As already explained above, the integrated gas discharge lamps 5 can have communication means or at least one communication interface, which in particular which enables communication with the on-board electronics of the motor vehicle. Particularly advantageous appears a LIN bus, but also the connection of the integrated gas discharge lamp by means of a CAN bus and the on-board electronics is possible.

Through the communication interface, the lamp can be advantageously connected to the higher level control system, e.g. communicate with a light module in a car. In this case, various information about the integrated gas discharge lamp 5 can be transmitted to the higher-level control system via the communication interface. This information is stored in a non-volatile memory in the lamp. The production of the integrated gas discharge lamp 5 produces a variety of information which can be collected by the production plant and programmed towards the end of the production of the lamp in the non-volatile memory of the lamp. However, the information can also be written directly into the nonvolatile memory of the operating electronics of the integrated gas discharge lamp 5, therefore a communication interface for this purpose is not absolutely necessary.

During production, for example, the gas discharge lamp burner 50 is measured exactly and attached to the pedestal 70 with respect to a reference plane of the base in a precisely defined position on the base. This ensures a high quality of the optical system consisting of integrated gas discharge lamp 5 and headlight 3, since the arc burning between the gas discharge lamp electrodes 504 assumes an exact spatial position relative to the reference plane, which is the interface to the headlight. The production machine is characterized, for example, the distance and the position of the electrodes known. However, the electrode spacing can be an important variable for the operating electronics since the electrode spacing of the gas discharge lamp burner 50 correlates with the burning voltage.

Furthermore, a unique serial number or alternatively a production batch number can be stored in the non-volatile memory of the lamp in order to ensure traceability. Via the serial number, the data stored in the integrated gas discharge lamp 5 parts can be queried with all available data via a database maintained by the manufacturer to identify the affected lamps in production errors of individual parts can.

In a preferred embodiment of the integrated gas discharge lamp 5, further parameters measured during lamp operation and stored in the nonvolatile memory of the integrated gas discharge lamp 5 can be interrogated and also stored via the on-board electronics by means of the communication interface. It may be useful, for example, to store the data of the optical system of which the headlight is made in the integrated gas discharge lamp 5, since it can thus control the power of the gas discharge lamp burner 50 in such a way that a uniformly high light output of the headlight system is achieved.

As communication parameters in particular the following communication parameters come into question:

The cumulative burning time of the gas discharge lamp burner 50,

- the number of flicker effects that have occurred, ie the Number of exceedances of the permissible limit value, the number of starts of the flicker minimum search, the current lamp power, the current frequency of the inverter, - the lamp power setpoint (= target lamp power), the actual value of the lamp power, the temperature of the electronics, the serial number or batch number, - the total number of lamp extinguishers and the number of lamp extinguishers within a given time span, eg 200 h, - the number of non-ignitions.

In principle, a conventional operating electronics not integrated in the lamp socket of the discharge lamp would also have been able to detect these parameters and make them available via a communication interface. However, these parameters would not have been useful for a diagnosis in the context of the service of the motor vehicle, since the lamp could have been changed at any time independently of the operating electronics and consequently the read-out parameters need not necessarily describe the currently existing system of lamp and operating electronics. This disadvantage does not have the described system of an integrated gas discharge lamp, in which a gas discharge lamp burner and an operating electronics for the gas discharge lamp burner are integrated inseparably from each other in a lamp.

The communication interface is preferably a LIN bus or alternatively a CAN bus. Both interface protocols are widely used in the automotive sector and introduced. If the integrated gas discharge lamp 5 is not used in an automobile, the communication interface of the integrated gas discharge lamp 5 can also have a protocol that is widely used in general lighting, such as DALI or EIB / Instabus.

On the basis of these data (in particular the cumulative burning time), the higher-level control system present in the motor vehicle can be used e.g. calculate the expected replacement time of the integrated gas discharge lamp 5. At an inspection date of the vehicle can then be decided whether the integrated gas discharge lamp 5 will work properly until the next inspection date, or whether it must be replaced, for example, a poor quality of light or even a failure of the lamp must be feared.

By virtue of the fact that the data can be read out via a communication interface of the integrated gas discharge lamp, a service technician can read the data from the integrated gas discharge lamp and replace the lamp if necessary, as described above with regard to a flickering lamp.

If data from the production of the integrated gas discharge lamp is permanently stored in the non-volatile memory of the operating electronics, the lamp can be used at any time in its lifetime calculations

Using data, which makes the lifetime calculations, that is, the estimate of the duration of how long the integrated gas discharge lamp will work properly, become significantly more accurate. Preferably, in the nonvolatile memory of the operating electronics are data stored, from which the production period can be opened. In this way, any defective productions or defects detected later in a batch can still be exchanged in the field before the lamp fails. This is of very great use for the user of the motor vehicle, because in particular when using the integrated gas discharge lamp in a headlight, it is a particularly safety-relevant application. If data stored in the non-volatile memory of the operating electronics, by means of which the integrated gas discharge lamp is uniquely identified, the data stored in a database during production can be simply and reliably assigned to the lamp. This works particularly efficiently when a unique and unique serial number is stored in the non-volatile memory of the operating electronics. This includes, among other things, a manufacturer code agreed by all manufacturers, so that although different manufacturers of the same type of integrated gas discharge lamp can assign a serial number in their respective production, it is nevertheless ensured that there will be no second lamp which is the same Serial number owns.

During operation of the integrated gas discharge lamp, one or more numbers are preferably stored in the non-volatile memory, which increase monotonically with the burning time and / or with the number of ignitions of the gas discharge lamp. In this case, the burning time of the gas discharge lamp burner is detected, added up and stored as a cumulative burning time in the nonvolatile memory of the operating electronics. The cumulative fuel duration is preferably stored as a number in nonvolatile memory. However, the burning time can also be weighted by operating parameters and stored in the nonvolatile memory of the operating electronics as a number, this number then corresponding to the cumulative weighted burning time. The different types of cumulative burning time will be discussed in more detail below. Thus, the previous burning time can be reliably compared with the specified life of the manufacturer, and an accurate statement about the remaining life of the lamp are made. The lifetime specified by the manufacturer can be a function of further data likewise read from the nonvolatile memory, so that it can depend, for example, on the number of starts or the required luminous flux of the lamp. The decision as to whether the integrated lamps must be replaced can also be made for economic reasons by the data stored in the diagnostics device of the service workshop, which were determined in the context of the previous workshop visits, and thus, for example, the information on how intensive the light used within the previous service intervals was included in the decision to be made.

If a number stored in the nonvolatile memory of the operating electronics makes a statement about the flickering of the lamp, in particular the number of starts of the flicker minimum search or the current flicker limit, the state of the integrated gas discharge lamp can be accurately detected and read out as required ,

These values can be used in a service of the motor vehicle, in which the integrated gas discharge lamp is located, be used to assess the remaining life with. Also of interest to the service technician is the number of ignitions of the gas discharge lamp burner stored in the nonvolatile memory of the operating electronics, since the number of ignitions has as much influence on the service life as the burning time. At a service appointment of the car. Thus, data are read from the non-volatile memory of the operating electronics and depending on the data is a different approach to maintenance. This makes maintenance more efficient and better, early failures are rare and customer satisfaction increases. The decision as to whether the integrated gas discharge lamp has to be exchanged can, in addition to the experience of the service technician, be based on the data read from the nonvolatile memory of the operating electronics. The decision to replace the integrated gas discharge lamp is preferably made when the cumulative burning time and / or the cumulative weighted burning time and / or the number of ignitions of the gas discharge lamp burner is above a certain limit. The limit value preferably depends on the production period and / or on the data which permit a clear identification of the integrated gas discharge lamp. This makes a reliable and simple decision about the replacement of the integrated gas discharge lamp possible.

lumen Konstanz

However, the information stored in the non-volatile memory of the integrated gas discharge lamp 5 can also be be used to keep the light output of the integrated gas discharge lamp 5 constant over its lifetime. The light output at nominal power of gas discharge lamps changes over their lifetime. As the burning time increases, the efficiency of the lamp decreases due to blackening and devitrification of the discharge vessel, as a result of the burn-back of the electrodes and the consequent change in the discharge arc. The efficiency of the entire optical system is thereby further worsened, since these systems are usually dimensioned for a point light source or for the shortest discharge arc resulting from the minimum electrode spacing, and more light is lost in the optical system when the discharge arc is extended , Also, the optical system itself loses efficiency during its service life, whether through lens opacification or defocusing due to temperature cycling or the permanent vibration experienced by an automotive headlamp. In the following, a lamp burn time t _k , and a cumulatively weighted burn time t _{kg are} discussed, wherein the cumulatively weighted burn time t _{kg is} weighted with a weighting function γ explained below.

Since the operating electronics of the integrated gas discharge lamp 5 has stored the relevant parameters of the gas discharge lamp burner 50 in the nonvolatile memory, it can adapt the operating power P _LA applied to the gas discharge lamp burner 50 to its cumulative burning time. Since the aging process is not linear, a compensation function .beta. Is stored in the operating electronics in a simple embodiment it is shown in Fig. 27. Here, the cumulative weighted burning time t _{kg of} the lamp is plotted against the quotient of the lamp power P _LA to the nominal power P _{N of} the gas discharge lamp burner 50. In the lower range under 10h burning time the performance is slightly increased. This should help to condition gas discharge lamp burners 50. This is also known as "burning" of the gas discharge lamp burner 50 of the integrated gas discharge lamp 5. If the lamp is burned, it is operated with slightly reduced power (about 90% of the rated power), since the efficiency of the lamp as well as the optics is still very good From a cumulative weighted burning time t _kg of about 100 h, the power slowly increases again to reach a lamp power P _La which is about 10% higher than the specified rated nominal lamp burner power when the specified end-of-life of 3000 h The light output of the gas discharge lamp burner over its burning time substantially constant. The stored in the operating electronics function can be used in non-volatile

Memory in the production stored burner parameters, such. be influenced by the electrode spacing.

In an advanced system with a control of the integrated gas discharge lamp 5 by a higher-level control system, further light functions, such as the speed-dependent control of the amount of light emitted, can be realized. In such an advanced embodiment, the operating electronics are designed to operate the gas discharge lamp torch 50 with under or over power. However, if the gas discharge lamp burner 50 is not equipped with nominal operated, it ages differently than in a nominal power operation. This must be taken into account in the calculation of the cumulative burning time. For this purpose, a weight function γ is stored in the operating electronics, which represents a factor which depends on the over- or underpower. FIG. 28 shows the weight function γ for an integrated gas discharge lamp 5 designed for use in the headlight of a motor vehicle. If the gas discharge lamp burner 50 is operated with excess power, it ages faster because the electrodes become too hot and the electrode material evaporates. If the gas discharge lamp burner 50 is operated with significant underpowering, it will also age faster because the electrodes are too cold and subsequently sputter electrode material, thus electrode material is removed by sputtering, which is undesirable because this reduces the life of the lamp and the light output. Therefore, the operating electronics of the integrated gas discharge lamp 5 must include this aging in the cumulative weighted burning time t _kg . This can be achieved, for example, by

The following formula can be achieved: t _kg (t) = \ f (τ) -χ (- ^) dτ;

the function f (τ) stands for the burning function only, i. when the gas discharge lamp burner 50 is in operation, f (τ) = 1, when the gas discharge lamp burner 50 is not in operation, f (τ) = 0. If the integrated gas discharge lamp 5 is thus operated with over or under power, it ages by a factor which can reach the value 10 faster.

In an advanced control system comprising the gas discharge lamp burner 50 with over or under can also implement an advanced communication with the higher-level control unit. This can be expressed to the effect that the higher-level control unit no longer requests a specific power from the integrated gas discharge lamp 5, but rather a predetermined amount of light. In order to accomplish this, a dimming curve is stored in the operating electronics of the integrated gas discharge lamp 5. FIG. 29 shows such a dimming curve α using the example of an integrated gas discharge lamp 5 for the automotive industry. The dimming curve shows the dependence of the luminous flux φ _SoU emitted by the gas discharge lamp burner 50 or, as shown in FIG. 29, the luminous flux normalized to the nominal luminous flux φ _N.

Ström, from the electric burner power P _La , _s ,

or, as shown in FIG. 29, the electrical current normalized to the nominal rated nominal electrical power P _N

P _LaS see burner performance -. In Fig. 29 this is included

a cumulative weighted burning time t _{kg of} the gas discharge lamp burner 50 of 100 h applied. For another cumulative weighted burning time t _{kg of} the gas discharge lamp burner 50, other curves are obtained. Ideally, a three-dimensional characteristic map is stored in the operating electronics of the integrated gas discharge lamp 5, which takes into account the age of the gas discharge lamp burner 50. FIG. 29 is thus merely a section through the characteristic diagram for a cumulative weighted burning time t _{kg of} the gas discharge lamp burner of 100 h. The characteristic map for determining the lamp power can be calculated in addition to the luminous flux and the cumulative Weighted burning time contain other dimensions, such as the burning time since the last ignition of the lamp or the estimated burner temperature in particular effects in the range up to a few minutes after ignition, due to thermal transients during the so-called "run-up" of the lamp in which it The dimming curve does not necessarily have to be stored as a characteristic diagram in the operating electronics of the integrated gas discharge lamp 5, it can also be stored as a function, so that it can be calculated by a microcontroller integrated in the operating electronics To be able to implement the calculation of the lamp power to be set as simply as possible, the underlying function or the corresponding characteristic field can be expressed approximately by a product, wherein as factors in addition to the nominal power P _{N of} the gas discharge lamp burner every single factor describes the influence of one of the above sizes. Thus, the required burner power P _La for a given amount of light can be exemplified by the following formula

are: P _La = P _N ; the factor ß is taken into account

Here, the aging of the gas discharge lamp burner 50. The function ß may also include the aging of the optical system, these data are preferably communicated via the communication interface of the integrated gas discharge lamp, so that these influences can also be considered in the calculation of the operating electronics of the integrated gas discharge lamp. The amount of light predetermined by the control unit can be, for example, the speed of a motor vehicle depend in which the integrated gas discharge lamp 5 is operated. For example, when driving slowly, the lamp is operated in dimmed mode, whereas at high speeds, it is operated slightly above the rated power, for example on the motorway, in order to ensure a clear view and a good illumination of the road.

In an advanced operating electronics of a further embodiment of the integrated gas discharge lamp 5, the previous combustion duration of the gas discharge lamp burner 50 can also or additionally be taken into account during operation. As the cumulative weighted firing time tkg approaches the specified end-of-life of the gas discharge lamp burner, the operating electronics may operate the burner at a rate that causes it to age least, thus effectively extending its life compared to conventional operation. FIG. 30 shows such an exemplary burner curve in which the luminous flux quotient 1 lies above the

cumulative normalized lifetime - is plotted.

The latter is calculated from the lamp burn time t _k divided by the rated life t _{N of} the lamp of, for example, 3,000 hours. Up to 3% of its rated life, the gas-discharge lamp burner 50 is operated at 1.2 times its rated power to condition and burn-up the gas discharge lamp burner 50. Thereafter, the gas discharge lamp burner 50 is operated at rated power for a long time. If the gas discharge lamp burner 50 reaches 80% of its service life, the power is successively increased to approximately 0.8 times the nominal reduced. The weight function in Fig. 28 discloses, on closer inspection, that the lamp is spared the most in operation at approximately 0.8 times its rated power. Therefore, the integrated gas discharge lamp 5 is operated at the end of its life with this power to ensure the longest possible residual life and a sudden lamp failure, which can have fatal consequences especially in the automotive sector. Instead of the lamp burn time t _k , the cumulative weighted burning time t _kg can be used, contrary to the illustration in FIG. 30.

The integrated gas discharge lamp 5 can calculate the expected remaining life of its gas discharge lamp burner based on the above-mentioned data and calculations and in a non-volatile memory of the

Store operating electronics 220, 230. If the motor vehicle is in an inspection in the workshop, interesting lamp data, in particular the stored remaining service life, can be read out for the inspection. Based on the read remaining life can then be decided whether the integrated gas discharge lamp 5 must be replaced. It is also conceivable that in the integrated gas discharge lamp 5, the serial number of the integrated gas discharge lamp and / or the serial number of the gas discharge lamp burner 50 is stored. On the basis of the serial number, the mechanic in the workshop can query via a manufacturer database whether the lamp is in order or may need to be replaced due to defects in the production or in the components installed in it. In a further advantageous embodiment of the integrated gas discharge lamp 5, contrary to the above-described embodiment in the workshop not the expected remaining life is read, but it read the data as the lamp was actually operated. These data are then evaluated by the diagnostic device based on the nominal data associated with each serial number from the manufacturer database. For example, the rated life t _{N of} a lamp with a given serial number is stored in the manufacturer database. In the case of product defects this would be correspondingly low. After further data about the operation in the operating electronics are stored, such as the number of ignitions, these parameters can also be compared with the manufacturer's database, which then contains, for example, the number of nominal ignitions for each lamp. A read from the operating electronics high number of ignitions that comes in the vicinity of the nominal ignitions, thus leading to the decision that the lamp is replaced, although, for example, the rated life of the lamp has not yet been reached. By using such criteria, the availability of the light source increases in an economical manner. This procedure is to be regarded as economical, in particular, because a lamp is replaced only when the probability is high that its failure is imminent. The first bit of the serial number of the lamp encodes the lamp manufacturer to ensure that the serial number remains unique, although, if appropriate, several lamp manufacturers make interchangeable products. When querying nominal data such as the rated service life or the nominal ignitions from the Manufacturer database, via a communication link between the workshop and the lamp manufacturer, for example via an Internet connection, in turn, the transmitted data from the operating electronics data on the operation of the lamp manufacturer. There is thus a bidirectional data exchange between operating electronics of the lamp and the manufacturer database. This makes it possible, on the one hand, to track products in the field, in particular a statistical survey of the mode of use of the product, which is particularly advantageous for product development, but individual data collection is also possible if, for example, the VIN (Vehicle Identification Number ) of the vehicle is transmitted. In addition, the possibility of protection against counterfeiting opens up. The latter is achieved by also having to copy the serial number during a counterfeiting of the product, which ultimately leads to a seeming inconsistency in the data when transmitting the data to the manufacturer, since, for example, the operating hours attributed to a serial number are not reduced again what an appropriate conclusion on counterfeit products allows.

arc straightening

A method for straightening the discharge arc of the gas discharge lamp burner, which is implemented in one embodiment of the integrated gas discharge lamp 5, will now be described below. For a first embodiment, an operating electronics 920 is used, which has a topology according to FIG. 23. has. In this case, the operating electronics 920 has a DC-DC converter 9210, which is supplied by the battery voltage of an automobile. The DC-DC converter 9210 is connected downstream via an intermediate circuit capacitor C _zw an inverter 9220, which supplies a lamp circuit comprising a gas discharge lamp burner 50 with an AC voltage. The lamp circuit consists of an output capacitor C _A and the ignition electronics 910, with the primary winding of the ignition transformer in the lamp circuit, and the gas discharge lamp burner 50th

By means of this topology, which is well known from the prior art, with a skillful design of the components, a straightening of the discharge arc can be achieved.

A straightened discharge arc offers many advantages.

A first important advantage is the better thermal budget of the gas discharge lamp burner 50, obtained by a more uniform thermal wall load of the burner vessel. This leads to a better thermal utilization and thus longer life of the burner vessel. A second significant advantage is a contracted arc that has reduced diffusivity. With such a 'narrower' bow, e.g. The optics of a headlight can be made more precise and the light output of the headlight can be increased significantly.

Since in the integrated gas discharge lamp 5 the ignition and operating electronics 910, 920 or the overall operating electronics 930 (also referred to below as operating electronics) are inseparably connected to the gas discharge lamp torch 50, the operating electronics can calibrate themselves on the gas discharge lamp burner 50 to create a stable burning straight arc. Since due to the inseparability of operating electronics 920, 930 and gas discharge lamp burner 50 of the operating electronics 920, 930 and the burning time of the gas discharge Lambrenners 50 is known, aging effects of the gas discharge lamp burner 50 may affect the operation of the gas discharge lamp burner 50.

The basic procedure for straightening the arc of the integrated gas discharge lamp 5 is as follows: The operating electronics 920, 930, when switched on for the first time, measure the gas discharge lamp burner 50 with respect to acoustic resonances and detect the frequencies suitable for bowing. This is done by scanning the frequency ranges between a minimum frequency and a maximum frequency. The frequencies are modulated to the operating frequency of the integrated gas discharge lamp burner. During scanning, the impedance of the gas discharge lamp burner is measured and the lowest impedance at the corresponding frequency is stored in each case. This frequency with the lowest impedance characterizes the maximum achievable arc straightening. Depending on the lamp type, the minimum frequency can drop to a frequency of 8OkHz, the maximum frequency can reach a frequency of about 30OkHz. In a typical automotive high pressure discharge lamp, the minimum frequency is about 110 kHz and the maximum frequency is about 160 kHz. The measurement is necessary to compensate for manufacturing tolerances of the gas discharge lamp burner 50. The typical aging with respect to the resonance frequencies of the lamp is in a microcontroller (not shown) of the operating electronics 920, 930, for example, stored in a table. Optionally, the values in the table may be stored depending on the operation of the gas discharge lamp burner (cycle shape, start-up or dimmed operation). In addition, in another embodiment, the controlled operation may be extended by a controlled modulation mode having a modulation frequency in a narrow range around the calculated frequency (in accordance with the controlled operation). The calculated frequency is modulated with a modulation frequency of eg 1 kHz in order to prevent possible flicker phenomena by excitation of acoustic resonances in the gas discharge lamp burner 50. An advantage over previous prior art devices is that the frequency range (within which the frequency may be varied) is now very small, and the problems with dimming lamps or unstable regulator behavior are smaller. Nevertheless, it may be useful for certain lamp types to measure the frequency ranges by the actual modulation frequency with respect to their Flackerverhaltens to ensure stable lamp operation can. For this purpose, in one embodiment, the circuit arrangement is used for detecting flickering, and measures frequencies lying close to the modulation frequency for their flicker behavior.

In a first embodiment according to FIG. 23, the frequency of the DC-DC converter 9210 is now selected equal to the modulation frequency. By appropriate design of the DC link capacitor C _zw remains a high-frequency ripple as aufmodulierte high-frequency AC voltage on the DC-DC converter 9210th output DC voltage. The DC voltage with the modulated high-frequency AC voltage serves as the input voltage for the inverter 9220. The inverter 9220 is designed here as a full bridge, which converts the DC voltage into a rectangular AC voltage. The amplitude of the modulation signal, ie the modulated high-frequency alternating voltage, is determined by the dimensioning of the output filter of the full bridge (output capacitor C _A ) and by the inductance of the secondary winding (IPSH, IPSR) of the pulse ignition transformer. Because these components are inseparably connected to each other in the integrated gas discharge lamp 5, a good matching of the components to the desired mode of operation is possible. Due to the superimposed high-frequency voltage, the desired straightening of the discharge arc occurs. The disadvantage of this embodiment is the fixed-frequency operation of the DC-DC converter, which does not allow effective switching discharge, so that the losses of the system increase.

In a second embodiment according to FIG. 24, the superimposed high-frequency voltage is generated by a signal generator 9230. This couples in the high-frequency voltage in the lamp circuit between a choke L _κ and the primary winding of the ignition transformer of the ignition electronics 910 a. The coupling in front of the ignition transformer is important, since the Signal Generator 9230 would otherwise have to be designed with high voltage resistance. The throttle is used to decouple the _{DC link capacitor} C _zκ , otherwise he would steam the coupled high-frequency voltage too much. For this reason, the inductance should also be Ignition transformer 910 should be as small as possible. The signal generator can be designed so that the frequency of the injected high-frequency voltage is in turn modulated in order to achieve a safer and flicker-free operation of the gas discharge lamp burner 50.

In a third embodiment, shown in FIG. 25, the signal generator is integrated with the ignition electronics 910. Here, the gas discharge lamp burner 50 is started by a resonance ignition. The ignition electronics has a designed for high-frequency operation ignition transformer Ti _R , which is controlled by a signal generator, which is designed as a class-E converter. The ignition transformer T _ΣR is to be dimensioned so that the at least the fundamental of the occurring high frequency and identical to the switching frequency of the class E converter is still sufficiently well transmitted, in particular its efficiency at this frequency is better than 10%. The switching frequency of the class E converter during ignition is between 80 kHz and 10 MHz. Preferably, however, the frequency is chosen above 300 kHz because a small design is possible here and below 4 MHz since the achievable efficiencies are particularly high. The ignition transformer is controlled via a galvanically isolated primary winding. The secondary winding is divided into two galvanically isolated windings, each connected between a lamp electrode and the inverter 9220. The signal generator generates here a high-frequency current through the primary winding of the ignition transformer T _ΣR , on the secondary side excites a resonance in a resonant circuit which causes the gas discharge lamp burner 50 to break. The resonant _circuit consists of the secondary _{inductance of} the ignition transformer T _ΣR and a _lying over the lamp capacitance C _R 2. Since the capacitance C _R 2 is very small, it does not necessarily have to be integrated as a component in the ignition electronics 910, but can by structural measures are generated.

As soon as the gas discharge lamp burner 50 has ignited, the mode of operation of the signal generator is changed over, so that it now injects a high-frequency signal via the ignition transformer Ti _R , which is modulated onto the lamp voltage for arc straightening. This has the advantage that the frequency and the amplitude of the modulated voltage is relatively freely adjustable, without having to forego an optimized operation of the DC-DC converter 9210 or the inverter 9220. By this circuit topology can be provided by the ignition electronics 910 also generated via the resonant circuit increased transfer voltage for the gas discharge lamp burner 50, so that it does not have to be generated by the DC-DC converter 9210. With this measure, the operation of the DC-DC converter 9210 can be further optimized because the necessary output voltage range of the DC-DC converter 9210 is smaller. Also, the inverter 9220 must implement less power, as part of the lamp power is coupled in via the modulated lamp voltage. This embodiment thus offers the greatest freedom in the implementation of the operating parameters, so that an optimized and reliable operation of the Gas discharge lamp burner 50 is possible with straightened discharge arc.

FIG. 26 shows an embodiment of a DC-DC converter 9210 which is simplified in comparison to the prior art. The DC-DC converters for ballasts which can be operated on an electrical system of an automobile and which are customary in the prior art have a flyback converter topology, which is also referred to as flyback. Since the on-board voltage of 12V must be increased to a higher voltage. Because of that in the integrated

Gas discharge lamp 5, the electrical contact takes place only when the lamp in the headlamp 3, a simplified converter in the form of a boost converter, also referred to as a boost converter, with an autotransformer T _FB can be used. This is possible because in the electromechanical interface used an accidental contacting of the converter output with vehicle ground, which would have a destruction of the boost converter result, can be excluded. The DC-DC converter used in the prior art in flyback converter topology allow an interruption of the energy flow despite output short circuit. This is not the case in the present converter concept according to FIG. 26, since there is no galvanic isolation in the power path of the converter which inadvertently mixes the energy flow from the input, ie the 12V vehicle electrical system, to the output, ie to the power supply of the gas discharge lamp burner 50 with the vehicle ground connected, could interrupt. Otherwise, the DC-DC converter is constructed in the usual way. It consists of an input side EMI filter, an input capacitor Cl, a converter switch Q, designed as an autotransformer inductance T _FB , which operates via a diode D to the intermediate _circuit capacitor C _zw . This converter is considerably less expensive than the blocking transducers used in the prior art, thus the integrated gas discharge lamp 5 is considerably more cost-effective compared to a lamp system according to the prior art, with a gas discharge lamp and an external electronic operating device in the system consideration.

Reference sign list

20 electronic control gear

210 electrical contact 220 electrical contact

230 electrical contact

240 electrical contact

3 headlights

33 reflector of the headlamp 35 carrier part with mating contacts

350 mating contacts

351, 352 slots

5 Integrated gas discharge lamp

50 gas discharge lamp burner 502 discharge vessel

504 electrodes

506 molybdenum foil

52 Metal clamp for holding the gas discharge lamp burner 53 Holding plate for metal clamp

54 metallic coating of the outer bulb

56 sockelnahe power supply of the gas discharge lamp burner

57 Remote power supply 70 lamp base

702 reference ring

703 emerging from the reference ring

burl

705 Retaining clip for gas discharge lamp 7051 Slot into which the retaining clip hooks

7053 bulge in the retaining clip

71 sealing ring to the reflector

72 electrically conductive housing 722 tabs 73 sealing ring between base plate and

base

74 base plate

741 base plate dome

80 Ignition transformer 81 Ferrite core

811 first ferrite core half

8110 first half of the inner part of the ferrite core

8112 side wall of the first ferrite core half 81121 elongated recesses

812 second ferrite core half 814-816 Conclusion ferrites 8120 second half of the inner part of the

ferrite core

8122 side wall of the second ferrite core half

81221 oblong depressions

821 hollow cylinder

822 round plates

823 slot

824 hollow cylindrical center core

825 first plate

826 second plate

827 paragraph

85 contact body

851 first roof area

852 second roof area

86 primary winding

861, 863,

865 Cylindrical inward-pointing curves

862, 864 Tabs for el. Contacting 8620,8640 Radii or curves at the ends of the sheet metal strip of the primary winding

866-869 fastening straps for mech. attachment

87 secondary winding

871 inner end of the secondary winding

872 outer end of the secondary winding

910 ignition electronics

920 operating electronics

930 total operating electronics

9210 DC-DC converter

9220 inverter

9230 signal generator

Claims

claims

A method of operating an integrated gas discharge lamp (5) comprising a gas discharge lamp burner

(50), an operating electronics (920) and an ignition electronics (910), wherein the operating frequency of the integrated gas discharge lamp (5) starting from a lower limit frequency at a low cumulative burning time (t _k ) over the burning time of the gas discharge lamp burner (50) integrated Gas discharge lamp (5) up to a final value at a cumulative burning time, which is close to the specified life of the gas discharge lamp burner

(50) of the integrated gas discharge lamp (5) is increased.

2. A method for operating an integrated gas discharge lamp (5) according to claim 1, characterized in that the operating frequency remains constant at a lower cutoff frequency until a cumulative burning time of about 10% - 20% of the rated life of the gas discharge lamp burner (50), then during the cumulative following burning period to 40% - 60% is successively increased by about 0.5 Hz / h to a first upper limit frequency, to then stay at the first upper limit frequency

3. A method for operating an integrated gas discharge lamp (5) according to claim 2, characterized in that the operating frequency until a cumulative burning time of about 500 h constant at about

400 Hz, then continuously during the cumulative burning time of about 500 h to about 1500 h 0.5 Hz / h is increased to about 900 Hz, to stay from then at about 900 Hz.

4. A method for operating an integrated gas discharge lamp (5) according to claim 1, characterized by the following steps

2. wait for a predetermined time, 3. increase the operating frequency by a predetermined first frequency, 4. repeating steps 2 and 3 n times

5. A method for operating an integrated gas discharge lamp (5) according to claim 4, marked thereby, that the cumulative first burning time between

10% and 20% of the rated life of the gas discharge lamp burner (50) is the predetermined time I h -

20 h, the first frequency is between 1 Hz and 50 Hz, and n = 16 ... 256.

6. A method for operating an integrated gas discharge lamp (5) according to claim 4 or 5, characterized in that the operating frequency increases from a cumulative burning time of 2097152 s always after the expiration of 32768 s 128 times by 4 Hz each up to a final value of 912 Hz becomes.

7. A method for operating an integrated gas discharge lamp (5) according to claim 1, characterized in that the operating frequency from a cumulative second burning time in one step from a lower Limit frequency is increased to a first upper limit frequency.

8. A method for operating an integrated gas discharge lamp (5) according to claim 7, marked thereby, that the cumulative second burning time between 5% and 20% of the rated life of the gas discharge lamp burner (50), the lower cutoff frequency between 100 Hz and 500 Hz , and the first upper limit frequency is between 600 Hz and 900 Hz,

9. A method for operating an integrated gas discharge lamp (5) according to claim 8, characterized in that the operating frequency is increased from a cumulative burning time of 1048576 s in one step from a frequency of 400 Hz to a frequency of 800 Hz.

10. A method of operating an integrated gas discharge lamp (5) according to claim 1, characterized in that the operating electronics comprises a detection circuit for detecting flickering of the arc of the gas discharge lamp burner (50), and from a cumulative burning time of the gas discharge lamp burner of about 16% of The following steps are carried out during the rated service life: stepwise increase of the operating frequency of the gas discharge lamp burner (50) from the lower limit frequency to the first upper limit frequency, - measurement of the flickering intensity of the arc of the gas discharge lamp burner (50) at the selected one

11. A method for operating an integrated gas discharge lamp (5) according to claim 1, characterized in that the operating electronics comprises a detection circuit for detecting flickering of the arc of the gas discharge lamp burner (50), and from a cumulative burning time of the gas discharge lamp burner of about 16% of Rated life following steps are repeated:

Stepwise increasing the operating frequency of the gas discharge lamp burner (50) from the lower limit frequency up to a second upper limit frequency,

Measurement of the flicker intensity of the arc of the gas discharge lamp burner (50) at the selected operating frequency,

- As soon as the Flackerintensität falls below a predetermined threshold setting the operating frequency to the current frequency and termination of the process.

12. A method for operating an integrated gas discharge lamp (5) according to claim 11, characterized in that the second upper limit frequency is between 600 Hz and 900 Hz.

13. A method for operating an integrated gas discharge lamp (5) according to claim 11, characterized in that in the absence of falling below the predetermined threshold Flackerintensität the second upper limit frequency is tripled.

14. Integrated gas discharge lamp (5), which carries out a method according to claims 1-13.