Method for producing a tube lamp and corresponding tube lamp

Abstract

A method for producing a tube lamp uses at least one leadframe. A leadframe is a flat structure which has two opposing surfaces extending substantially parallel and spaced apart by the sheet thickness. One or more stabilizing sections are applied to the leadframe. The leadframe is fastened with the stabilizing sections in a tubular housing of the tube lamp.

Claims

1. A method for producing a tube lamp, the method comprising: providing at least one leadframe, wherein the leadframe is substantially planar in form; applying one or more stabilizing sections to the leadframe; and fastening the leadframe in a tubular housing of the tube lamp using the stabilizing sections, wherein the one or more stabilizing sections are structurally distinct from the tubular housing.

2. The method according to claim 1, wherein the one or more stabilizing sections are made from at least one of a thermoplastic material and a glass.

3. The method according to claim 2, wherein fastening the leadframe in the tubular housing using the stabilizing sections comprises: heating the stabilizing sections to a temperature at which the stabilizing sections are molten; and adhering the leadframe to the tubular housing using the stabilizing sections.

4. The method according to claim 1, wherein fastening the leadframe in the tubular housing using the stabilizing sections comprises: applying an adhesive to at least several of the stabilizing sections; and adhering the stabilizing sections of the leadframe to the tubular housing with the adhesive.

5. The method according to claim 1, wherein applying one or more stabilizing sections to the leadframe comprises: providing a material jet for the stabilizing section; and moving the leadframe through the material jet.

6. The method according to claim 1, wherein applying one or more stabilizing sections to the leadframe comprises: positioning a bar or individual bar sections made from a material of the stabilizing section on the leadframe; heating the bar or the bar sections; and pressing the bar or the bar sections on the leadframe.

7. The method according to claim 1, wherein: providing at least one leadframe comprises providing a panel having a plurality of leadframes which are arranged adjacent to one another; and applying one or more stabilizing sections to the leadframe comprises applying at least one stabilizing section as a continuous stabilizing section over at least two leadframes arranged adjacent to one another.

8. The method according to claim 7, wherein applying at least one stabilizing section as a continuous stabilizing section over at least two leadframes arranged adjacent to one another comprises providing at least one continuous stabilizing section with at least one predefined breaking point.

9. A tube lamp comprising: a tubular housing; a light engine arranged at least partially inside the tubular housing, the light engine comprising a leadframe, wherein the leadframe is substantially planar in form; and one or more stabilizing sections mounted on the leadframe, wherein: the one or more stabilizing sections are structurally distinct from the tubular housing; and the leadframe is fastened in the tubular housing using the one or more stabilizing sections.

10. The tube lamp according to claim 9, wherein the one or more stabilizing sections are made from a thermoplastic material.

11. The tube lamp according to claim 9, wherein the leadframe is adhered to the tubular housing by the one or more stabilizing sections.

12. The tube lamp according to claim 9, wherein the leadframe is adhered to the tubular housing by an adhesive applied to the one or more stabilizing sections.

13. The tube lamp according to claim 9, wherein the one or more stabilizing sections are made from a glass.

14. The tube lamp according to claim 9, wherein the one or more stabilizing sections are made from an electrically insulating material.

15. The tube lamp according to claim 9, wherein the leadframe is configured as an electrically conductive structure that functions without an electrically insulating substrate or an electrically insulating flexible layer.

16. The tube lamp according to claim 9, wherein the leadframe is comprised of an electrically conductive metal.

17. The tube lamp according to claim 9, wherein the light engine further comprises at least one semiconductor light element arranged on and electrically connected to the leadframe.

18. The tube lamp according to claim 9, further comprising at least one electronic driver component arranged on and electrically connected to the leadframe.

19. The tube lamp according to claim 9, wherein the one or more stabilizing sections extend over a width of the leadframe, substantially perpendicular to a longitudinal length of the leadframe.

20. The tube lamp according to claim 9, wherein the one or more stabilizing sections are configured to both: stabilize the leadframe inside the tubular housing; and bridge spacing between the leadframe and the tubular housing.

21. The tube lamp according to claim 9, wherein the one or more stabilizing sections are mounted on at least two opposing sides of the leadframe.

22. The tube lamp according to claim 9, wherein the one or more stabilizing sections extend through an interior space of the leadframe, contacting at least two opposing sides of the leadframe.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Preferred further embodiments of the invention are explained in greater detail by the following description of the drawings. In the drawings:

(2) FIG. 1 shows an embodiment of a tube lamp according to the present invention;

(3) FIG. 2 shows a leadframe for a tube lamp without stabilizing sections;

(4) FIG. 3 shows the leadframe according to FIG. 2 with a two-sided stabilizing section;

(5) FIG. 4 shows the leadframe according to FIG. 3 from another view;

(6) FIG. 5 shows an embodiment of a tube lamp according to the present invention;

(7) FIG. 6 shows a panel with a plurality of leadframes and stabilizing sections;

(8) FIG. 7 shows a detail of a panel with a plurality of leadframes and with stabilizing sections with predefined breaking points; and

(9) FIG. 8 shows an individual leadframe from the panel according to FIG. 7.

DETAILED DESCRIPTION OF PREFERRED EXEMPLARY EMBODIMENTS

(10) Preferred exemplary embodiments are described below with reference to the drawings. In this case elements which are the same, similar, or act in the same way are provided with identical reference numerals in the different drawings, and repeated description of some of these elements is omitted in order to avoid redundancies.

(11) Directional details such as “at the top”, “at the bottom”, “right” and “left” referred to below relate to the representation in den drawings.

(12) FIG. 1 shows schematically an embodiment of an LED retrofit tube lamp according to the present invention in cross-section (perpendicular to the longitudinal direction). The tube lamp has a tubular housing 1. A leadframe 2 with a plurality of leadframe elements 3 is arranged in the interior of the housing 1. LEDs fastened to the upper surface of the leadframe 2 are not shown in this illustration.

(13) A stabilizing section 4 extends on the lower surface of the leadframe 2 over the plurality of leadframe elements 3 and connects these mechanically to one another. The stabilizing section 4 consists of an electrically non-conductive material (for example made from a hot melt adhesive), so that no electrical connection is produced between the leadframe elements 3 by the stabilizing section 4.

(14) The stabilizing section 4 has extensions 5, which extend through the intermediate spaces between the leadframe element 3 and are spread on the other side of the leadframe 2 and at least partially abut the upper surface of the leadframe 2. As a result a non-positively and a positively engaged connection take place between the leadframe 2 and the stabilizing section 4.

(15) Furthermore, the stabilizing section 4 is in non-positively engaged, in particular adhesive connection to the inner side of the tubular housing 1. In other words, by means of the stabilizing section 4 the leadframe 2 is adhered to the tubular housing 1.

(16) FIG. 2 shows schematically a leadframe 2 for a tube lamp without stabilizing sections. The leadframe 2 has a plurality of leadframe elements 3, between which LEDs 6 are fastened (for example soldered). It can be clearly seen from this illustration that in a leadframe without stabilizing sections a high loading of the solder points and/or LEDs can occur. Also the lower continuous leadframe element 3′ is not connected to the other leadframe elements 3 by means of a long region (in the extreme case over the entire length of the leadframe 2, which in so-called 5-foot lamps can amount to almost 150 cm).

(17) In FIG. 3 the leadframe 2 according to FIG. 2 is shown schematically with a stabilizing section 4. The stabilizing section 4 connects a plurality of leadframe elements 3, 3′ along both surfaces of the leadframe 2. The stabilizing section 4 consists of an electrically non-conductive material (for example made from a hot melt adhesive), so that no electrical connection is produced between the leadframe elements 3 by the stabilizing section 4.

(18) The stabilizing section 4 can also extend through the intermediate spaces between the leadframe element 3, 3′. As a result a non-positively and a positively engaged connection take place between the leadframe 2 and the stabilizing section 4.

(19) In FIG. 4 the leadframe 2 of FIG. 3 can be seen from another view (from below). Here it is shown schematically that an adhesive 7 (for example a hot melt adhesive, a two-component adhesive or an adhesive which cures under UV radiation) is applied to the underside of the stabilizing section 4, by which the stabilizing section 4 can be connected to a housing 1 of a tube lamp.

(20) The illustration according to FIG. 5 shows schematically an embodiment of a tube lamp according to the present invention. Here the leadframe 2 according to FIG. 3 and FIG. 4 is arranged in a tubular housing 1 of a tube lamp. The stabilizing sections 4 are connected by non-positive engagement by means of the adhesive 7 to the inner side of the tubular housing 1. The stabilizing section 4 bridges a large part of the distance between the leadframe 2 and the tubular housing 1. In this way only a small amount of the adhesive 7 is required, so that in particular the handling of the leadframe 2 is simplified when it is installed in the tubular housing 1.

(21) FIG. 6 shows schematically a panel 8 with a plurality of leadframes 2 and stabilizing sections 4. The panel 8 contains seven leadframes 2, which are still connected to one another by connecting sections 9. It may also be provided that a panel having a different number of leadframes can be used. The panel 8 further comprises a frame 10, which is likewise connected by means of connecting sections 9 to the leadframe 2. The panel 8 can be produced for example by stamping or cutting out from a metal sheet.

(22) At a plurality of locations on the panel 8 stabilizing sections 4 extend opposite one another along both surfaces of the leadframe 2 over the entire width of the panel 8. In the illustration only two locations with stabilizing sections 4 are shown, but stabilizing sections 4 can be provided over the entire length of the panel 8 and thus of the leadframe 2.

(23) The stabilizing sections 4 can also extend through the intermediate spaces between the leadframes 2. As a result a non-positively and a positively engaged connection are produced between each leadframe 2 and the stabilizing section 4.

(24) FIG. 7 shows schematically a detail of a panel 8 with a plurality of leadframes 2. Here too, stabilizing sections 4 extend opposite one another along both surfaces of the leadframe 2 over the entire width of the panel 8. In each case between two leadframes 2 as well as between the outermost leadframe 2 and the frame 10 of the panel 8 the stabilizing sections 4 are provided with predefined breaking points 11 which are formed as U-shaped indentations. The predefined breaking points 11 enable the stabilizing sections 4 to part easily at the respective location in order to separate the leadframes 2.

(25) FIG. 8 shows schematically a detail of an individual leadframe from the panel according to FIG. 7. There are still no LEDs fastened on the leadframe 2, so that the leadframe elements 3, 3′ are only held together by the stabilizing sections 4.

(26) Alternatively LEDs can also be already mounted on the leadframe 2 before the separation of the leadframes 2 of a panel 8.

(27) Although the invention has been illustrated and described in greater detail by the depicted exemplary embodiments, the invention is not restricted thereto and other variations can be deduced therefrom by the person skilled in the art without departing from the scope of protection of the invention.

(28) In general “a” or “an” may be understood as a single number or a plurality, in particular in the context of “at least one” or “one or more” etc., provided that this is not explicitly precluded, for example by the expression “precisely one” etc.

(29) Also, when a number is given this may encompass precisely the stated number and also a conventional tolerance range, provided that this is not explicitly ruled out.

(30) If applicable, all individual features which are set out in the exemplary embodiments can be combined with one another and/or exchanged for one another, without departing from the scope of the invention.

LIST OF REFERENCES

(31) 1 tubular housing 2 leadframe 3, 3′ leadframe elements 4 stabilizing section 5 extent of the stabilizing section 6′ LED 7 adhesive 8 panel 9 connecting section 10 frame 11 predefined breaking point