NOZZLE FOR A HOT GAS WELDING TOOL AND METHOD OF MANUFACTURING A LIGHTING DEVICE

Abstract

A nozzle including a coupling portion, intended to be coupled to at least two hot gas outlets of a welding tool, and a transition portion, connected to the coupling portion. The transition portion has a first width in the connection between the transition portion and the coupling portion, and has a second width in an end opposite to the connection between the transition portion and the coupling portion, the second width being greater than the first width.

Claims

1. Nozzle for a hot gas welding tool, the hot gas welding tool comprising at plurality of hot gas outlets, the nozzle comprising a coupling portion, intended to be coupled to at least two hot gas outlets of the welding tool, a transition portion, connected to the coupling portion; the transition portion having a first width in the connection between the transition portion and the coupling portion, and having a second width in an end opposite to the connection between the transition portion and the coupling portion, the second width being greater than the first width.

2. Nozzle according to claim 1, further comprising an outflow portion connected to the transition portion in the end of the second width, the outflow portion having a first width in the connection between the transition portion and the outflow portion, and having a second width in the end opposite to the connection between the transition portion and the outflow portion, the second width being at least the same as the first width.

3. Nozzle according to claim 2, wherein the area of the cross section of the outflow portion in the connection between the transition portion and the outflow portion is lower than the area of the cross section of the coupling portion.

4. Nozzle according to claim 2, wherein the second width of the outflow portion is higher than the first width of the outflow portion.

5. Nozzle according to claim 2, wherein the outflow portion has walls, the thickness of the walls being lower than 0.5 mm.

6. Nozzle according to claim 1, wherein the transition portion has a first height in the connection between the transition portion and the coupling portion, and has a second height in the end opposite to the connection between the transition portion and the coupling portion, the second height being lower than the first height.

7. Nozzle according to claim 1, further comprising flow aligners, the flow aligners being suitable for orienting a hot flow coming from the coupling portion towards a direction closer to the direction of the fluid exiting the hot gas outlets.

8. Nozzle according to claim 7, wherein the flow aligners comprise at least one of balls, grains, grid elements, mesh elements, wherein the distance between two adjacent flow aligners is lower than the third part of the first height of the transition portion.

9. Nozzle according to claim 7, wherein the flow aligners are located in the coupling portion.

10. Nozzle according to claim 7, wherein the flow aligners have a melting temperature higher than 100 C.

11. Nozzle according to claim 7, wherein the flow aligners have a characteristic dimension lower than 0.5 mm.

12. Nozzle according to claim 1, which is at least partially made of metal, particularly aluminium or steel.

13. Nozzle according to claim 1, wherein the coupling portion comprises tubes intended to be coupled to at least two hot gas outlets of the welding tool.

14. Nozzle according to claim 1, wherein the coupling portion is tangent in at least part of its surface to at least part of the hot gas outlets where the nozzle is intended to be coupled to.

15. Method of manufacturing an automotive lighting device, the method comprising the steps of providing a hot gas welding tool with hot gas outlets, such that the hot gas welding tool comprises at least a nozzle according to claim 1, installed in a plurality of hot gas outlets, ejecting hot gas through the nozzle to weld pieces of the automotive lighting device.

16. Method according to claim 15, further including the step of tuning the position of the outlet portion of the nozzles before ejecting hot gas.

17. Nozzle according to claim 3, wherein the second width of the outflow portion is higher than the first width of the outflow portion.

18. Nozzle according to claim 3, wherein the outflow portion has walls, the thickness of the walls being lower than 0.5 mm.

19. Nozzle according to claim 2, wherein the transition portion has a first height in the connection between the transition portion and the coupling portion, and has a second height in the end opposite to the connection between the transition portion and the coupling portion, the second height being lower than the first height.

20. Nozzle according to claim 2, further comprising flow aligners, the flow aligners being suitable for orienting a hot flow coming from the coupling portion towards a direction closer to the direction of the fluid exiting the hot gas outlets.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0046] To complete the description and in order to provide for a better understanding of the invention, a set of drawings is provided. Said drawings form an integral part of the description and illustrate an embodiment of the invention, which should not be interpreted as restricting the scope of the invention, but just as an example of how the invention can be carried out. The drawings comprise the following figures:

[0047] FIG. 1 shows a schematic view of a nozzle according to the invention.

[0048] FIG. 2 shows a detail of flow aligners in a particular embodiment of a nozzle according to the invention.

[0049] FIG. 3 shows a first example of a hot gas welding tool.

[0050] FIG. 4 shows a detail of the welding tool of FIG. 3, where a nozzle according to the invention is press fitted.

[0051] FIG. 5 shows a second example of a hot gas welding tool.

[0052] FIG. 6 shows a detail of the welding tool of FIG. 5, where a nozzle according to another embodiment of the invention is press fitted.

[0053] FIG. 7 shows a welding tool comprising nozzles according to the invention, welding two parts of a lighting device by a method according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0054] FIG. 1 shows a schematic view of a nozzle 1 according to the invention. This nozzle 1 comprises [0055] a coupling portion 2, intended to be coupled to at least two hot gas outlets of the welding tool, [0056] an outflow portion 4, [0057] a transition portion 3, connecting the coupling portion 2 to the outflow portion 4.

[0058] The transition portion 3 has a first width w31 in the connection between the transition portion and the coupling portion, and has a second width w32 in the connection between the transition portion and the outflow portion, the second width w32 being greater than the first width w31.

[0059] Although present in the embodiments shown in these figures, the outflow portion 4 is not an essential element of the invention, since the transition portion 3 ends in a section with a greater width than the coupling portion 2. Hence, in other embodiments, the outflow portion 4 does not exist, and the gas reaches the parts to be welded from the end of the transition portion 3.

[0060] The outflow portion 4 has a first width w41 in the connection between the transition portion 3 and the outflow portion 4, and has a second width w42 in the end opposite to the connection between the transition portion 3 and the outflow portion 4, the second width w42 being the same as the first width w41. However, in other embodiments, the second width w42 could be also slightly higher than the first width w41.

[0061] The first width w41 of the outflow portion 4 is the same as the second width w32 of the transition portion 3, because the transition portion 3 ends in the same section as the outflow portion 4 starts.

[0062] In this nozzle 1, the area of the cross section of the outflow portion 4 in the connection between the transition portion 3 and the outflow portion 4 is lower than the area of the cross section of the coupling portion 2.

[0063] In this nozzle 1, the transition portion 3 has a first height h31 in the connection between the transition portion 3 and the coupling portion 2, and has a second height h32 in the connection between the transition portion 3 and the outflow portion 4, the second height h32 being lower than the first height h31.

[0064] This nozzle 1 of this embodiment is made of stainless steel, and the thickness t5 of the walls 5 of the outflow portion is less than 0.3 mm, so that fine tune may be made easily. However, other suitable materials and suitable thicknesses could be chosen for nozzles 1 according to different embodiments within the scope of the invention.

[0065] This nozzle 1 is suitable for being installed or being part of a hot gas welding tool.

[0066] This nozzle 1 further comprising flow aligners 7. These flow aligners 7 are present in the nozzle 1 to orient the hot flow coming from the hot gas welding tool. The flow aligners 7 are located in the coupling portion 2, in order to achieve that the flow velocity profile is flatter than in the coupling portion.

[0067] To achieve this aim, the flow aligners may be one of balls, grains, grid elements, mesh elements. The skilled person knows how a suitable pattern of one or more of these elements is adequate for making the hot flow be more oriented according to the longitudinal direction, and therefore the heat contained in this flow may be more useful for the welding of the lighting device parts.

[0068] FIG. 2 shows a detail of these flow aligners in a particular embodiment of a nozzle according to the invention. In this figure, it can be observed how the distance between two adjacent flow aligners is lower than the third part of the first height h31 of the transition portion 3: more than three rows of grids are comprised in the first height 31, so the distance between two grids is lower than the third part of the first height h31. This figure shows a grid, but, as stated before, any other element suitable for this purpose is considered within the scope of this invention.

[0069] These flow aligners have a characteristic dimension lower than the thickness of the nozzle, for a good thermal behaviour of the nozzle.

[0070] FIG. 3 shows a hot gas welding tool 10 with a plurality of hot gas outlets 11. These hot gas outlets 11 comprise a portion of a tube 12, so that part of this portion outstands from the welding tool 10.

[0071] FIG. 4 shows a detail of the welding tool 10 of FIG. 3, where a nozzle 1 according to the invention is press fitted. In this embodiment, the nozzle 1 of the invention is press fitted against the parts of the portion of tubes 12 which outstands the welding tool 10. For this purpose, the coupling portion 3 of the nozzle 1 is externally tangent in at least part of its surface to at least part of the portion of tubes 12 installed in the hot gas outlets 11 where the nozzle 1 is intended to be coupled to.

[0072] FIG. 5 shows a hot gas welding tool 10 with a plurality of hot gas outlets 11. These hot gas outlets 11 do not comprise a portion of a tube, so that part of this portion outstands from the welding tool 10.

[0073] FIG. 6 shows a detail of the welding tool 10 of FIG. 5, where a nozzle 1 according to another embodiment of the invention is press fitted. In this embodiment, the nozzle 1 of the invention comprises tubes 6 intended to be coupled to at least two hot gas outlets 11 of the welding tool 10. The tubes 6 of the nozzle 1 are press fitted against the hot gas outlets 11 of the welding tool 10. For this purpose, the tubes 6 are internally tangent in at least part of its surface to at least part of the hot gas outlets 11 where the nozzle 1 is intended to be coupled to.

[0074] FIG. 7 shows a welding tool 10 comprising nozzles 1 according to the invention, each nozzle 1 being installed in a pair of hot gas outlets 11. This welding tool 10 is welding two parts of a lighting device by ejecting hot gas through the nozzle 1.