EP2052399B1 - Method for the production and insertion of an electrode frame comprising a lamp coil into a discharge vessel of a discharge lamp - Google Patents

Abstract

The invention relates to a method for producing and inserting an electrode frame (1') comprising a lamp coil (6) into a discharge vessel (7) of a discharge lamp. In said method, the following steps are carried out: a) two separate electrode holders (2', 3') are provided in the form of substantially elongate wires; b) an elongate brace (8) is fastened to the two spaced-apart electrode holders (2', 3'); c) the lamp coil (6) is mounted on forward end regions (21, 31) of the electrode holders (2', 3'); d) some sections of the electrode frame (1') produced in steps a) to c) are inserted into the discharge vessel (7).

Description

Technical area

The invention relates to a method for manufacturing and introducing an electrode frame with a lamp filament into a discharge vessel of a discharge lamp.

State of the art

From the DE 10 2004 004 655 A1 a low-pressure discharge lamp is known, which has an at least partially extending into a discharge vessel electrode. The electrode comprises an electrode frame, which electrode frame comprises two current-carrying electrode holders made of Vakuvit wire. At the front ends of these two separate electrode holders a lamp coil is attached. This subarea is located inside the discharge lamp. Also within this discharge vessel is a glass bead, which connects the two electrode holders and holds them. In the area in which the glass bead is attached, the electrode holders are bent like a bottle neck.

In Fig. 1 Such a discharge lamp known from the prior art with a corresponding electrode frame is shown schematically. The electrode frame 1 comprises the two electrode holders 2 and 3, which are connected to a glass bead 5 in a tapered curved region 4 arranged within a discharge vessel 7. At the front ends of the electrode holders 2 and 3 extends transversely across a lamp filament 6. At a lower end region 71 of the discharge vessel 7, the outwardly guided electrode holders 2 and 3 are squeezed and fused into the material, so that the discharge vessel 7 is closed gas-tight at this end region 71. Between the glass bead 5 and the end region 71, a so-called wiping edge 72 is formed, which represents the lower limit of the phosphor coating of the discharge vessel 7.

The electrode frame 1 extends relatively far into the discharge vessel 7, whereby the discharge space is reduced. This results in a distance d1 between the lamp coil 6 and the lower end portion 71 of about 20 mm. Furthermore, a distance d2 between the lamp filament 6 and the glass bead 5 is dimensioned at about 10 mm.

In Fig. 2 an enlarged view of the electrode frame 1 is shown. It can be seen that in the tapered region 4, in which the glass bead 5 is formed drop-like, the two electrode holders 2 and 3 are arranged very close to each other.

The known electrode frame 1 is produced on the so-called FSP (Fußspannmaschine) in several successive manufacturing steps. For this purpose, first the individual wires of the electrode holders 2 and 3 are directed, the wires cut, the frame geometry bent accordingly and thus bent the two electrode holders 2 and 3 in their shown shapes, placed the glass bead 5, the electrode frame 1 bent into its final shape, the Glass bead 5 melted, the electrode holders 2 and 3 planed, bent at the front end portions of the electrode holders 2 and 3 hooks to then insert the lamp filament 6 there and can jam. In the following, a Spreizmaß the electrode holders 2 and 3 is then bent, the lamp filament 6 bepastet, bent a final final dimension and then then the electrode frame 1 inserted into a frame feed.

The glass bead serves to stabilize the electrode frame 1 during handling between the individual processing steps up to the crushing of the end region 71. Disadvantages of this design with a glass bead are the fact that a special glass, for example OG131, is required as an expensive material for this purpose , A current insulation up to temperatures of about 600 ° C must be guaranteed, which is not possible with conventional soft glasses. In addition, in the solution with a glass bead 5 no safe EOL (End of Life) behavior is guaranteed. In operation, situations may occur in which, despite a broken lamp filament 6 power supplies to plastic parts and then melt them, since the glass bead 5 is conductive. In addition, pearl spots can occur in the burner positions. The known from the prior art production of such an electrode frame 1 and their introduction into the discharge vessel of a discharge lamp is relatively complex and also very expensive. In addition, during operation undesirable errors can occur, which can lead to damage or destruction of parts of the discharge lamp.

Presentation of the invention

It is therefore an object of the present invention to be able to simplify the production of such an electrode frame as well as the introduction of this into a discharge vessel and to be able to provide a more operationally robust electrode frame.

This object is achieved by a method having the features of claim 1.

In a method according to the invention for producing an electrode frame and for introducing such an electrode frame with a lamp filament into a discharge vessel of a discharge lamp, initially two separate electrode holders in the form of substantially elongated wires are provided. Furthermore, an elongated strut is attached to the two spaced apart electrode holders. At front end portions of the electrode holders, a lamp filament is mounted so that this lamp filament extends between the two electrode holders. The electrode frame produced in this embodiment is then introduced in regions in the discharge vessel, so that at least the lamp filament is disposed within the discharge vessel. In particular, by attaching an elongated cross member, the stability criterion of the electrode holders and thus also of the entire electrode frame can be ensured. The stability is at least as great as when mounting a propfenartigen glass bead. In addition, it can be achieved that the electrode holders in the region of this stabilizing element spaced apart from each other as in a design with a propfenartigen glass bead. Moreover, the elongate strut can be attached to the electrode holders much more easily and inexpensively, and is itself preferably made of materials which are much cheaper than expensive pearl glass, for example OG131.

According to the invention, the electrode frame is introduced into the discharge vessel such that the elongate strut is positioned outside the discharge vessel. In addition to the guaranteed stability of the electrode frame, this arrangement can also be used to ensure accessibility to the transverse strut at any time. Even after the gas-tight fusing and in particular after squeezing the end region of the discharge vessel, into which the electrode frame extends into the discharge vessel, a handling of this elongate strut can be carried out.

The elongate strut is preferably completely separated from the electrode holders after the zone-wise introduction of the electrode frame into the discharge vessel. This separation of the elongated strut preferably takes place after crushing of an end region of the discharge vessel for gastight sealing of the discharge vessel. The elongated strut thus serves during the manufacture and introduction of the electrode frame into the discharge vessel for stabilization and can be removed, in particular after squeezing, after the electrode frame has been mechanically stably arranged anyway.

Preferably, the elongate strut is separated prior to pumping the discharge vessel. Pumping means evacuating and filling the discharge vessel with a filling material.

The elongated strut is preferably at least 12 mm, in particular at least 15 mm, in particular at least 20 mm, spaced from the lamp filament attached to the electrode holders. By this spaced arrangement a significant shortening of the entire electrode frame can be achieved.

Preferably, the elongate strut is welded to the electrode holders. In this case, a welding process proves to be particularly suitable in accordance with resistance welding. The mechanically stable connection of the electrode frame can thereby be ensured during production and the primary introduction of the electrode frame into the discharge vessel.

The elongated strut preferably has a length between about 5 mm and 10 mm. In particular, the length of this cross member is about 7 mm. As a result of this configuration, it is possible for the electrode holders to be substantially more widely spaced from one another in the region of the attached elongate strut than is the case in the prior art with the formation of a prop-like glass bead. Short circuits between close to each other arranged electrode holders can be prevented.

Preferably, the elongate strut is formed as an electrically conductive element. In particular, it can be provided that the elongate strut is a wire, in particular a vacuum wire. Particularly in embodiments in which the electrode holders are made of such a wire, in particular a Vakuvit wire, and the elongate strut may be formed of a corresponding material. As a result, costs can also be saved in the procurement of materials, since an already provided wire can also be used for the elongated strut.

Preferably, the elongate strut has a diameter of about 0.4 mm. This also corresponds to the preferred diameter of the electrode holders. Such a thickness of the elongate strut allows for reliable attachment to the electrode supports and also provides sufficient stability and position retention of the electrode supports during insertion and further securing of the electrode support to the discharge vessel.

In particular, if the elongated strut is to be separated from the electrode holders after the end region of the discharge vessel has been squeezed, such an electrically conductive element can be used. Since this elongate strut is then removed anyway before the actual operation of the discharge lamp, a possible current bridge, as would then arise through the elongated strut, can be prevented.

However, it can also be provided that the elongate strut is formed of an electrically non-conductive material. For example, in this case also a stable plastic or the like may be provided. Also, this can be done in various ways on the electrode holders be attached, for example, a sticking, a clinging or the like may be mentioned. In this case, it can also be provided that an electrically nonconductive element with a corresponding temperature stability is formed, so that it can also be provided that this elongated strut is arranged inside the discharge vessel when the electrode frame is introduced into the discharge vessel and a pinch of the end region, on which the electrode frame is inserted, is completed. In such a material design of the elongate strut, it can remain permanently attached during operation of the discharge lamp, since a current bridge does not arise in this regard.

Preferably, the elongate strut is formed with such a length that after attachment of the strut to the electrode mounts, the distance between the two electrode mounts in the region of the attached strut substantially the distance of the two electrode mounts to the front end portions where the lamp filament is mounted, equivalent. A variety of bending and forming a tapered, bottle-like portion of the electrode holders, as required in the formation of a glass bead in the prior art, can be prevented thereby.

As a result of the embodiment and production according to the invention, it can also be achieved that the electrode frame must protrude less far into the discharge vessel than in the prior art Fig. 1 the case is. As a result, it is also possible to achieve an extension of the discharge space in the discharge vessel, since with such a pearl-free one Electrode racks the lamp filament can be lowered to a so-called wiping edge. Since a shorter electrode frame can thus also be achieved with the invention, the wire saved thereby can be used for an electrode holder, in particular for the elongate strut. Compared to the prior art, at most the same amount of wire is used, which already gives a cost-saving potential here.

In addition, the degree of use can be increased because no pearl bursting can occur. Furthermore, an increase in performance of the Fußspannmaschine can be achieved, since geometriebiegungen and a Perleneinschmelzen, as required in the art, omitted. In addition, since no power transmission takes place, as may occur, for example, in the case of the glass bead in the prior art, the discharge lamp is also EOLproof. Also maintenance costs for bending tools and a melting burner for introducing the glass bead can be saved.

Short description of the drawing (s)

Fig. 1

ein Entladungsgefäß einer Entladungslampe mit einem aus dem Stand der Technik bekannten Elektrodengestell;

Fig. 2

eine vergrößerte Darstellung des bekannten Elektrodengestells gemäß Fig. 1;

Fig. 3

eine momentane Fertigungsphase eines erfindungsgemäßen Elektrodengestells beim Einbringen in ein Entladungsgefäß einer Entladungslampe; und

Fig. 4

eine vergrößerte Darstellung eines erfindungsgemäßen Elektrodengestells in einem weiteren Fertigungsschritt.

An embodiment of the invention will be explained in more detail with reference to schematic drawings. Show it:

Fig. 1

a discharge vessel of a discharge lamp with an electrode frame known from the prior art;

Fig. 2

an enlarged view of the known electrode frame according to Fig. 1 ;

Fig. 3

a momentary manufacturing phase of an electrode frame according to the invention when introduced into a discharge vessel of a discharge lamp; and

Fig. 4

an enlarged view of an electrode frame according to the invention in a further manufacturing step.

Preferred embodiment of the invention

In the figures, identical or functionally identical elements are provided with the same reference numerals.

In Fig. 3 a manufacturing state of an electrode frame 1 'is shown in a schematic representation, which is introduced into a discharge vessel 7 of a discharge lamp. The electrode frame 1 'is made in its basic production of two electrode holders 2' and 3 ', a lamp filament 6' and an elongate strut 8. For this purpose, two separate pieces of wire are initially provided. In the exemplary embodiment, the electrode holders 2 'and 3' are made of a vacuum wire and have substantially the same length. In a further production step, an elongate strut 8 is then fastened between the electrode holders 2 'and 3' arranged substantially parallel to one another. The elongated strut 8 is also formed in the embodiment of Vakuvit wire and has a diameter of about 0.4 mm, which also corresponds to the diameter of the two electrode holders 2 'and 3'. The elongate strut 8 is introduced as a transverse strut between the two electrode holders 2 'and 3' and is attached to both electrode holders 2 'and 3'. attached by resistance welding. As can be seen from both the presentation in Fig. 3 as well as from the enlarged partial view according to Fig. 4 can be seen, the elongated strut 8 is set back to front end portions 21 and 31 of the electrode holders 2 'and 3'. In the embodiment, the distance d4 between these front end portions 21 and 31 of the electrode holders 2 'and 3' to the elongate strut 8 is about 15 mm.

As both from the representation in Fig. 3 as well as from the representation in Fig. 4 can be seen, extend the two electrode holders 2 'and 3' substantially parallel over its entire length. Both electrode holders 2 'and 3' have no tapered region, as in the prior art according to Fig. 1 and Fig. 2 in area 4 is required. The electrode holders 2 'and 3' thus have a substantially constant distance d3 over their entire length. This is in the exemplary embodiment about 7 mm and thus corresponds substantially to the length of the elongated strut 8.

After welding the elongate strut 8 to the two electrode holders 2 'and 3', the wires are planarized. Subsequently, hooks are then bent at the front ends 21 and 31, and subsequently the lamp filament 6 is inserted into these bent hooks and clamped there. Then a Spreizmaß the electrode holders 2 'and 3' is bent and the lamp filament 6 is pasted. Then follows a bending of the final dimension of the electrode frame 1 'and an insertion of this in the rack feed. In this state of manufacture, the electrode frame 1 'is in its basic provision completed. Subsequently, this electrode frame 1 'is then introduced into the discharge vessel 7. For this purpose, the front region, to which the lamp filament 6 is fastened, is introduced at an end region 71 of the discharge vessel 7 into the discharge space. This follows in the embodiment so far that the elongate strut 8 is still outside the discharge vessel 7.

The electrode frame 1 'is inserted into the discharge vessel 7 so far that a distance d5 between the lamp filament 6 and the lower edge region of the end region 71 is formed. This is in the exemplary embodiment about 10 mm and is thus substantially smaller, in particular by half smaller than the distance d1 in the conventional embodiment according to Fig. 1 , The electrode frame 1 'must therefore be introduced far less into the discharge vessel 7, whereby the discharge space can be increased in comparison to the prior art.

The distance d4 between the lamp filament 6 and the elongate strut 8 is, as already explained, in the exemplary embodiment about 15 mm. As can be seen, the electrode frame 1 'and thus also the lamp filament 6 extend at the front ends 21 and 31 of the electrode holders 2' and 3 'by a relatively small value beyond the wiping edge 72 into the discharge vessel 7.

Starting from this in Fig. 3 Subsequently, the end region 71 is heated and squeezed in the following, so that the electrode holders 2 'and 3' are pinched in position stable manner in this end region 71 are and this end portion 71 is sealed gas-tight.

Subsequently, the elongated strut 8 is then separated from the electrode holders 2 'and 3', in which, for example, cutting takes place with a corresponding cutting tool. After the separation of this elongate strut 8 then the pumping operation takes place in the discharge vessel 7, in which this is evacuated and appropriate filling material is introduced.

In the Fig. 4 shown enlarged view of the electrode frame 1 'shows a manufacturing state after the actual parts assembly of the electrode frame 1' and prior to introduction into the discharge vessel. 7

Claims (9)

1. Method for manufacturing and introducing an electrode frame (1') with a lamp filament (6) into a discharge vessel (7) of a discharge lamp, in which method the following steps are performed:

   a) providing two separate electrode holders (2', 3') in the form of substantially elongate wires;

   b) fastening an elongate strut (8) onto the two electrode holders (2', 3'), which are arranged spaced apart from one another;

   c) attaching the lamp filament (6) to front end regions (21, 31) of the electrode holders (2', 3');

   d) introducing regions of the electrode frame (1') manufactured in steps a) to c) into the discharge vessel (7),

   characterized in that
   the electrode frame (1') is introduced into the discharge vessel (7) in such a way that the elongate strut (8) is positioned outside of the discharge vessel (7).
2. Method according to Claim 1,
   characterized in that
   the elongate strut (8) is separated from the electrode holders (2', 3') once the regions of the electrode frame (1') have been introduced into the discharge vessel (7).
3. Method according to Claim 2,
   characterized in that
   the strut (8) is separated off once an end region (71) of the discharge vessel (7) has been pinch-sealed.
4. Method according to Claim 2 or 3,
   characterized in that
   the strut (8) is separated off prior to the pumping of the discharge vessel (7).
5. Method according to one of the preceding claims,
   characterized in that
   the elongate strut (8) is fastened on the electrode holders (2', 3') so as to be at least 12 mm, in particular at least 15 mm, in particular at least 20 mm, spaced apart from the lamp filament (6).
6. Method according to one of the preceding claims,
   characterized in that
   the elongate strut (8) is welded to the electrode holders (2', 3'), in particular is fastened thereto by means of resistance welding.
7. Method according to one of the preceding claims,
   characterized in that
   the elongate strut (8) is formed so as to be electrically conductive.
8. Method according to Claim 7,
   characterized in that
   the elongate strut (8) is a wire, in particular a Vakuvit wire.
9. Method according to one of the preceding claims,
   characterized in that
   the elongate strut (8) has such a length that, once the strut (8) has been attached to the electrode holders (2', 3'), the distance (d3) between the two electrode holders (2', 3') in the region of the strut (8) substantially corresponds to the distance (d3) between the two electrode holders (2', 3') at the front end regions (21, 31).

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