DE102009051537A1 - Burner-protected lamp - Google Patents

Abstract

The lamp has an outer bulb which has areas with different wall thicknesses. For a lamp output of 70 W and less, the neck area has a wall thickness of up to a maximum of 1.5 mm, preferably 0.8 to 1.1 mm, and a second area has a wall thickness of at least 1.7 mm and for a lamp output greater than 70 W. the neck area has a wall thickness up to a maximum of 2.0 mm, preferably 1.0 to 1.3 mm, and a second area has a wall thickness of at least 2.2 mm.

Description

Technical area

The invention relates to a space-protected lamp according to the preamble of claim 1.

State of the art

So far, the Platzerschutz is ensured by the so-called Shroud technique, see, for example WO 2007/122522 , Here, a thick-walled glass tube is arranged around the burner that is closed on both sides with metal caps and hereby also connected to the frame. When the burner bursts, the fast burner components are decelerated by this shroud and fall into the outer bulb, which is also created so that no glass stresses are generated by the hot, now slow burner components. Glass stresses that would cause breakage of the outer envelope are avoided by a suitable glass such as borosilicate glass. A disadvantage of this design is the complex and therefore expensive frame with the Shroud.

The DE 103 36 282 describes a lamp in which the burner is surrounded by two pistons, namely an inner evacuated piston and an outer thick-walled piston made of hard glass (Duranglas), which is filled with air and the still fast and hot when bursting of the burner and the inner piston Stops components and is not destroyed, which the Platzerschutz is guaranteed. This modular lamp has the disadvantage that the individual components, for example, the outer bulb based construction, must be made very accurately, and thus is relatively expensive.

Presentation of the invention

It is the object of the present invention to provide a lamp according to the preamble of claim 1, wherein in a cost-effective manner a Platzerschutz is made possible.

This object is achieved by the characterizing features of claim 1.

Particularly advantageous embodiments can be found in the dependent claims.

It is the object of the present invention to provide a lamp which prevents bursting of the hot burner components upon bursting of the burner by not breaking the outer bulb or unprotected parts of the outer bulb upon bursting of the burner, thus leaving the hot burner components in the lamp. In several embodiments, the function of this lamp will be explained.

One embodiment is a halogen lamp which is under high pressure during operation and may burst. A second embodiment is a high pressure discharge lamp having a quartz or ceramic burner with a metal halide fill or amalgam fill that may burst during operation. It preferably has an outer bulb of tempered glass (tungsten incandescent glass, borosilicate glass, aluminum silicate glass), soft glass (soda glass) or quartz glass can also be used, with a variation of the wall thickness, wherein the smaller wall thickness is in the Einschmelzbereich and is chosen such that a merging of the outer bulb with a base plate that holds a rack for the burner is possible. The outer bulb has at least a second larger wall thickness in the piston area, which is chosen so that when bursting the burner, the outer bulb is not destroyed. Usually, the outer bulb is equipped with a classic screw base or in particular for higher lamp powers an extended screw base which is fixed at a position on the outer bulb, where it has a relatively large wall thickness, and thus ensures that although the outer bulb in the region of the melt with small wall thickness can burst, but this area is surrounded by a cover. This cover is advantageous in particular an extended screw base, whereby the Platzerschutz is ensured, or it is a housing for electronics with an attached thereto screw base.

The space-protected lamp can be a metal halide lamp, a high-pressure sodium vapor lamp, in particular with high xenon pressure, z. B. 2 bar, a metal halide high-pressure discharge lamp or other high-pressure discharge lamp with a burner made of ceramic or quartz with a metal halide or amalgam filling with a screw base, an extended screw base or a housing for electronics with a screw be directly to the mains voltage or on magnetic or electronic ballast is operated. This lamp should have an outer bulb with areas of different wall thickness. In the area of melting or crushing with the smaller wall thickness, the wall thickness should be such that the outer bulb can be fused with the foot or the outer bulb can be squeezed into this area. In the remaining area of the outer bulb, a larger wall thickness is chosen, in such a way that when the burner bursts, the outer bulb remains intact. By way of example, in the case of a lamp having a metal halide-filled ceramic burner operated at a power of 70 W, a maximum wall thickness of 1.5 mm may be used Melting area, the foot are fused with the outer bulb, and are ensured by a wall thickness of at least 1.7 mm in the remaining area of the outer bulb of the Platzerschutz.

With increasing lamp power, greater than 70 W, the pistons generally become larger and have a greater wall thickness in the melting range of a maximum of 2.0 mm. In the same way but also increases with the power of the momentum of the burner components when bursting, which at higher lamp power, the wall thickness of the outer bulb to ensure the Platzerschutzes must also be greater, so should be at least 2.2 mm. In practice, this wall thickness may well be 3 mm and more. Overall, the wall thickness in the melting zone is always significantly smaller than the wall thickness in the remaining area of the outer bulb for both power ranges.

For the outer bulb, the use of mechanically and thermally stable hard glass, z. As borosilicate glass (Tungsten fused silica, Schott 8487, 8486 or Telux glass 410) aluminum silicate glass advantage. Because of the thick-walled glass and operating temperatures on the glass wall of well below 500 ° C and soft glasses, such as soda glasses, z. B. soda lime magnesia glass, alkaline earth alkali silicate glass (EMGO Glass 360 C, Schott AR glass) can be used.

Basically, the melting range is a weak point in the outer bulb, which can be protected by a cover. By using an extended screw base, z. B. with a sleeve of metal, z. B. made of aluminum, which may be constructed to protect against electrical voltages isolated to the outside, or from a plastic, for. As PBT, and the attachment of this extended screw base outside the thin Einschmelzbereiches is achieved that the outer bulb in the sensitive region of the meltdown can indeed be destroyed. But because of the surrounding extended screw base, the hot burner components can not escape from the lamp, thus the Platzerschutz is ensured.

Similarly, the electronics housing may also be attached to the outer bulb at a location outside the sensitive fusing area, which may burst this sensitive area, leaving the hot components but in the electronics housing, thus also providing burst protection is.

It is also possible a disc of mica on the two electrode wires or a disc of metal, for. B. aluminum over the glass base, whereby the fast burner components either slowed down or even stopped, thus protecting the sensitive Einschmelzbereich and bursting of the outer bulb is prevented.

A basic embodiment of an outer bulb is a bulbous or tubular shape, spherical or elliptical o. Ä., Each with a neck portion for sealing. It is essential here that the wall thickness for lamp powers of not more than 70 W in the region of the neck portion is 0.5 to 1.5 mm, preferably 0.8 to 1.2 mm. By contrast, the wall thickness in the area of the bulbous shape or tubular shape is at least 1.7 mm. The transition takes place in all forms as close as possible and quickly after the neck part. Similarly, for lamps having powers greater than 70 W, the wall thicknesses in the region of the neck portion are 0.5 to 2.0 mm, preferably 0.9 mm to 1.5 mm, and in the area of the bulbous or tubular form at least 2, 2 mm.

In a preferred embodiment, the outer bulb is bulbous. The wall thickness is also differentiated within the bulbous part. In this case, it is relatively small in a region close to the neck, which is convexly curved. At the point of inflection and a surrounding area it is larger, in the area of the maximum diameter it is again larger and in the dome area it can be largest. The increase in wall thickness from the thin fusing area to the thicker remaining area of the outer envelope is preferably in a range of 1 mm over a path length of 10 mm.

Because of the thick-walled outer bulb, lamps that are protected by light have a much greater weight and therefore a higher price than lamps that are not protected against space. In order to keep the weight and thus the price as small as possible, the minimum wall thickness outside the melting range should be as small as possible. For this solution of this optimization task the space-protected lamps are tested. For this, the American National Standard ANSI C78.387e-2003 to be used. In this test equipment and evaluation conditions for the test of space-protected lamps are specified, for lamps with quartz glass burners Annex A and for lamps with ceramic burners Annex B is used.

All in all, it should be noted that due to the greater hardness and the same burner wall thickness and the same power, lamps with ceramic burners require an outer bulb with a larger minimum wall thickness, approx. 0.4 mm more, outside the melting range than lamps with quartz glass burners.

Likewise, two conditions can be distinguished in these burst tests and their evaluation. At the first condition, the lamps pass the test just like that and under the tightened condition all lamps pass this test very surely. The difference is that in order to meet the more stringent conditions, the minimum wall thickness of the outer bulb outside the fusing area must be greater by about 0.6 mm than in the weaker test condition.

Brief description of the drawings

In the following, the invention will be explained in more detail with reference to several embodiments. The figures show:

1 a first embodiment of a lamp with tubular outer piston;

2 a second embodiment of a lamp with tubular outer piston;

3 an embodiment of a lamp with bulbous outer bulb;

4 a further embodiment of a lamp with bulbous outer bulb with attached Tellerfuß;

5 an embodiment of a lamp with screw base;

6 an embodiment of a lamp with a tubular piston with an extended screw base;

7 another embodiment.

Preferred embodiment of the invention

1 shows a first embodiment of a high-pressure discharge lamp 1 with a power of 70 W. It has a tubular outer bulb 2 that at one end by a bruise 3 is closed. At the bruise surrounds a pedestal 4 this end. The second end is through a dome 5 locked. Inside sits a discharge vessel made of quartz glass 6 that by a rack 7 with a short ( 7a ) and long power supply ( 7b ) is held. The outer bulb 2 is due to the high bulb wall temperature of quartz glass. The wall thickness is differentiated (not shown). In the area of bruising 3 it is the thinnest, in an area H, which is still covered 10 the socket is protected. Here the wall thickness is about 0.9 to 1.1 mm. This is followed by a transition region U, which extends approximately to the lower end of the discharge vessel 6 enough. Here, the wall thickness increases continuously. This is followed by a region A, in which the wall thickness is at least 1.7 mm. This area reaches here to the dome 5 , To fulfill the simple burst test, the wall thickness should preferably be at least 2.0 mm and at least 2.5 mm for safe performance of the burst test without damage. The region A means the part of the outer bulb, which comprises the largest part of the tube and possibly also the dome.

It is possible the thick-walled outer bulb in 1 be prepared so that a second tube is pushed onto the original tube before or after the melting, the inner diameter is only slightly larger than the outer diameter of the inner tube and whose length corresponds approximately to the length of the burner, and then with the inner tube is fused at the ends.

2 shows a further embodiment with similar outer bulb, but here is the discharge vessel 16 a ceramic burner. Since such discharge vessels burst with greater momentum, other dimensions of the outer bulb should be used here. A guideline is a 20% larger wall thickness.

3 shows the forerunner of a bulbous outer bulb for a lamp with 70 W and a burner made of ceramics made of borosilicate glass, which certainly the burst test after the ANSI C78.387e-2003 , Annex B exists. He is intended for a plate smelting. It is divided into a neck area 11 and a bulbous area 12 , The wall thickness H in the neck area is 1.0 to 1.15 mm here. This is followed by a transition region U to the region of maximum diameter of the outer bulb, which has a wall thickness U of at least 2 mm from the inflection point WP of the transition between the neck and stomach. In the area of the maximum diameter (A1), the wall thickness is at least 3 mm. Since the dome area is the most endangered, the wall thickness A2 should be at least 3 mm here. This value refers to the vertex.

4 shows a complete lamp 20 in which the bulbous outer bulb 12 from 3 with plate smelting 13 is used. It uses a 70 W ceramic torch with metal halide filling and an argon ignition gas.

In this lamp, a wall thickness of 0.8 mm to 1.3 mm is present after melting in the melting or neck area H, on average 1.1 mm. This is followed by a transition region in which the wall thickness U is about 1.8 to 2.2 mm. This area is almost still axially parallel to the longitudinal axis AX of the outer bulb. Until the turning point WP, the wall thickness increases to at least 3.0 mm too. It then remains approximately constant in the area of the remaining bulbous form. This applies in particular to the range of the maximum diameter (at A1) and the peak (A2).

This lamp ( 4 ) fulfills the burst test after the ANSI C78.387e-2003 in a safe way, which is characterized by the fact that after the burst test most of the tested lamps are still vacuum tight.

This lamp has a diameter of 65 mm and a length of 90 mm and a weight of about 110 g, which is comparable to the weight of a space-protected lamp in Shroud technology or in modular design. To reduce the weight, it is possible to reduce the wall thickness in the side and dome area by up to 0.6 mm to at least 2.4 mm, which, however, the burst test after the ANSI C78.387e-2003 no longer be met absolutely reliable.

In the case of a 150 W lamp 20 with a ceramic burner 25 according to 5 is selected as the wall thickness in the melting range 1.3 mm. To create a good vacuum in the outer bulb is a getter 21 used. To reduce the luminance and to prevent glare is in the bulbous outer bulb 12 a litter layer 24 , z. B. from Aerosil or cipernate introduced. An E27 screw base 26 is with a putty on the outer bulb 12 attached.

The minimum wall thickness at which the burst test is just passed is 2.7 mm, and the wall thickness at which the burst test passes without significant damage to the outer bulb is 3.3 mm. With even higher wattages, the wall thickness can be selected even higher for all values. In particular, it can be chosen at the points A1 and A2 between 3.5 and 4 mm. In the area of the inflection point 2.2 to 2.5 mm are useful, in the transition region U about 2.0 to 2.4 mm. In the neck area H, the preferred value is 1.5 mm. It should not be exceeded 2.0 mm. Here, however, it is true that with increasing wall thickness in the neck area the smelting area is less endangered when it bursts.

For the complete lamp according to 5 the ceramic discharge vessel sits obliquely to the lamp axis AX in the bulbous outer bulb. The frame 7 that the discharge vessel 25 Holds, is in the plate foot 28 fixed. The wall thickness of the outer envelope is not shown to scale. To properly protect the thinner areas of the outer bulb, the cover is 29 , which may include, for example, a ballast or ignitor, pulled up to a maximum about the inflection point of the bulbous outer bulb. To protect the meltdown is a per se known mica flakes 30 held on the frame. At the end of the cover sits a known screw base.

For a 35 W lamp, z. B. the wall thickness of 1.0 mm in the Einschmelzbereich and the minimum wall thickness at which the burst test is just passed to 2.1 mm and the minimum wall thickness at which the burst test passed safely will be chosen 2.7 mm. In the transition area, the mean values of 1.5 to 1.9 mm are selected accordingly. For smaller lamp power, the wall thickness can be further reduced. If the length of the lamp and the diameter of the outer bulb is reduced at the same time as the burner, which is usually shorter, it is possible to further reduce the weight of the lamp, so that, for example. B. receives a weight of 70 g or less in a lamp with a 20 W ceramic burner. Overall, a complicated separate protective device is avoided with such an outer bulb with differentiated wall thickness.

Preferably, the outer bulb is evacuated, wherein a getter is still housed in the outer bulb.

Other preferred embodiments include the following features:
Above the foot in the area of the electrode wires there is a mica disk, which can stop fast burner components, which are flying in the direction of the base, and thus protect the slightly weaker meltdown area.

Similarly, an aluminum disc can be pushed over the glass base, which also provides additional protection for the fusing area.

6 shows a further embodiment of a lamp 40 with normal screw base 45 ,

In a special embodiment, a special E27 screw base is attached, which in the upper area, z. B. with a cylinder or a cone made of an insulating material such as PBT, or a metal z. As aluminum, which may have an insulating layer, which may consist of a plastic material or an aluminum oxide layer, so that the electrical contactor is ensured.

At the turning point of a bulbous outer bulb, the wall thickness is preferably approximately the average of the values for H and A1. In particular, the actual value should not deviate more than 20% from this mean.

7 shows a full 100 W lamp 40 with a ceramic burner 39 and a tubular outer bulb 41 in plate smelting. The outer bulb is preferred 41 evacuated, with one more getter 21 is housed in the outer bulb. Above the foot in the area of the electrode wires is a mica disk 30 , This can stop fast burner components flying in the direction of the base, thus protecting the slightly weaker meltdown area.

Similarly, an aluminum disc can be pushed over the glass base, which also provides additional protection for the fusing area.

In the embodiment shown is a special E27 screw base 45 stated. This one is with a cover 46 extended in the way that it extends into the region of the thick-walled outer bulb and is fixed there in the usual way with a putty or an adhesive on the outer bulb. If the weak meltdown area should break when the burner bursts, the hot burner components remain inside the special E27 socket with extension part.

In the upper part of the extended screw base is an insulating material 47 , z. As Teflon, on the surface that overlaps the metallic screw thread something and thus ensures the contact protection.

Similarly, it is possible for this contact protection z. B. to realize with a cylinder or a cone of an insulating material such as PBT, or of a metal, for. As aluminum, which may have an insulating layer, which consists for example of a plastic material or an aluminum oxide layer.

• 1. Elektrische Lampe mit einer Längsachse, wobei ein innen liegender Brenner aus Keramik und Quarzglas von einem einseitig verschlossenen Außenkolben umgeben ist, der am ersten Ende mit einer Einschmelzung abgedichtet ist, einen Getter enthält und am zweiten Ende mit einer Kuppe verschlossen ist, dadurch gekennzeichnet, dass der Außenkolben in einen Halbereich, der an die Einschmelzung angrenzt, und einen das Entladungsgefäß umgebenden zweiten Bereich gegliedert ist, wobei die Wandstärke des Halsbereichs um mindestens 0,2 mm kleiner ist als die Wandstärke des zweiten Bereichs.
• 2. Elektrische Lampe nach Anspruch 1, dadurch gekennzeichnet, dass für Lampen mit Leistungen von 70 W und weniger die Wandstärke des Halsbereichs maximal 1,5 mm beträgt, vorzugsweise bei 0,8 bis 1,2 mm liegt und die Wandstärke des zweiten Bereichs bei mindestens 1,7 mm liegt.
• 3. Elektrische Lampe nach Anspruch 1, dadurch gekennzeichnet, dass für Lampen mit Leistungen von mehr als 70 W die Wandstärke des Halsbereichs maximal 2 mm beträgt, vorzugsweise bei 1,0 bis 1,3 mm liegt und die Wandstärke des zweiten Bereichs bei mindestens 2,2 mm liegt.
• 4. Elektrische Lampe nach Anspruch 1, dadurch gekennzeichnet, dass die Wandstärkeänderung zwischen dem Halsbereich und dem umgebenden zweiten Bereich innerhalb einer axialen Weglänge von 20 mm, vorzugsweise innerhalb 10 mm, erfolgt.
• 5. Elektrische Lampe nach Anspruch 1, dadurch gekennzeichnet, dass der zweite Teil des Außenkolbens rohrförmig ist.
• 6. Elektrische Lampe nach Anspruch 1, dadurch gekennzeichnet, dass der zweite Teil des Außenkolbens bauchig ist, mit einem maximalen Durchmesser, einem Scheitelpunkt und mit einem an den Halsbereich anschließenden Übergangsbereich.
• 7. Elektrische Lampe nach Anspruch 4, dadurch gekennzeichnet, dass die Wandstärke im Übergangsbereich 0,3 bis 0,5 mm größer als im Halsbereich ist.
• 8. Elektrische Lampe nach Anspruch 4, dadurch gekennzeichnet, dass zwischen Übergangsbereich und maximalen Durchmesser ein Wendepunkt liegt, in dem die Wandstärke mindestens 0,3 mm größer als im Halsbereich ist.
• 9. Elektrische Lampe nach Anspruch 4, dadurch gekennzeichnet, dass die Wandstärke im Punkt des maximalen Durchmessers mindestens 0,6 mm größer als im Halsbereich ist.
• 10. Elektrische Lampe nach Anspruch 4, dadurch gekennzeichnet, dass die Wandstärke im Bereich des maximalen Durchmessers bis zum Scheitel mindestens 3 mm beträgt.
• 11. Elektrische Lampe nach Anspruch 1, dadurch gekennzeichnet, dass der Außenkolben aus Hartglas, Quarzglas oder Weichglas gefertigt ist.
• 12. Elektrische Lampe nach Anspruch 1, dadurch gekennzeichnet, dass der Halsbereich außen von einer am Sockel befestigten Abdeckung umgeben ist.
• 13. Elektrische Lampe nach Anspruch 1, dadurch gekennzeichnet, dass die Einschmelzung von einer Quetschung oder von einer Tellereinschmelzung gebildet ist.

Essential features of the invention in the form of a numbered list are:

• 1. An electric lamp having a longitudinal axis, wherein an internal burner of ceramic and quartz glass is surrounded by a closed on one side outer bulb, which is sealed at the first end with a seal, contains a getter and is closed at the second end with a dome, characterized in that the outer bulb is subdivided into a neck region adjoining the meltdown and a second region surrounding the discharge vessel, the wall thickness of the neck region being at least 0.2 mm smaller than the wall thickness of the second region.
• 2. An electric lamp according to claim 1, characterized in that for lamps with powers of 70 W and less, the wall thickness of the neck region is a maximum of 1.5 mm, preferably 0.8 to 1.2 mm and the wall thickness of the second area at at least 1.7 mm.
• 3. Electric lamp according to claim 1, characterized in that for lamps with powers of more than 70 W, the wall thickness of the neck region is a maximum of 2 mm, preferably 1.0 to 1.3 mm and the wall thickness of the second region at least 2 , 2 mm.
• 4. An electric lamp according to claim 1, characterized in that the wall thickness change between the neck region and the surrounding second region within an axial path length of 20 mm, preferably within 10 mm occurs.
• 5. Electric lamp according to claim 1, characterized in that the second part of the outer bulb is tubular.
• 6. An electric lamp according to claim 1, characterized in that the second part of the outer bulb is bulbous, with a maximum diameter, a vertex and a subsequent to the neck region transition region.
• 7. An electric lamp according to claim 4, characterized in that the wall thickness in the transition region 0.3 to 0.5 mm larger than in the neck region.
• 8. An electric lamp according to claim 4, characterized in that between transition region and maximum diameter is a turning point, in which the wall thickness is at least 0.3 mm larger than in the neck region.
• 9. An electric lamp according to claim 4, characterized in that the wall thickness at the point of maximum diameter is at least 0.6 mm larger than in the neck region.
• 10. An electric lamp according to claim 4, characterized in that the wall thickness in the region of the maximum diameter to the apex is at least 3 mm.
• 11. Electric lamp according to claim 1, characterized in that the outer bulb is made of tempered glass, quartz glass or soft glass.
• 12. An electric lamp according to claim 1, characterized in that the neck region is surrounded on the outside by a cover attached to the base.
• 13. An electric lamp according to claim 1, characterized in that the melt is formed by a pinch or a plate smelting.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• WO 2007/122522 [0002]
• DE 10336282 [0003]

Cited non-patent literature

• American National Standard ANSI C78.387e-2003 [0017]
• ANSI C78.387e-2003 [0031]
• ANSI C78.387e-2003 [0034]
• ANSI C78.387e-2003 [0035]

Claims (13)

An electric lamp having a longitudinal axis, wherein an internal burner made of ceramic and quartz glass is surrounded by an outer bulb closed on one side, which is sealed at the first end with a seal, contains a getter and is closed at the second end with a dome, characterized in that the outer bulb is divided into a neck region which adjoins the meltdown and a second region which surrounds the discharge vessel, wherein the wall thickness of the neck region is smaller by at least 0.2 mm than the wall thickness of the second region. Electric lamp according to claim 1, characterized in that for lamps with powers of 70 W and less, the wall thickness of the neck region is at most 1.5 mm, preferably 0.8 to 1.2 mm and the wall thickness of the second region at least 1 , 7 mm. Electric lamp according to claim 1, characterized in that for lamps with powers of more than 70 W, the wall thickness of the neck region is a maximum of 2 mm, preferably 1.0 to 1.3 mm and the wall thickness of the second region at least 2.2 mm is located. An electric lamp according to claim 1, characterized in that the wall thickness change between the neck region and the surrounding second region within an axial path length of 20 mm, preferably within 10 mm takes place. Electric lamp according to claim 1, characterized in that the second part of the outer bulb is tubular. Electric lamp according to claim 1, characterized in that the second part of the outer bulb is bulbous, with a maximum diameter, a vertex and a subsequent to the neck region transition region. Electric lamp according to claim 4, characterized in that the wall thickness in the transition region 0.3 to 0.5 mm larger than in the neck region. Electric lamp according to claim 4, characterized in that between transition region and maximum diameter is a turning point, in which the wall thickness is at least 0.3 mm larger than in the neck region. Electric lamp according to claim 4, characterized in that the wall thickness at the point of maximum diameter is at least 0.6 mm larger than in the neck region. Electric lamp according to claim 4, characterized in that the wall thickness in the region of the maximum diameter to the apex is at least 3 mm. Electric lamp according to claim 1, characterized in that the outer bulb of hard glass, quartz glass or soft glass is made. Electric lamp according to claim 1, characterized in that the neck area is surrounded on the outside by a cover. An electric lamp according to claim 1, characterized in that the melting is formed by a pinch or by a plate smelting.

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