Method for manufacturing a lighting tube

Abstract

The housing 3 is made from a lighting tube 1 using 3D printing. In the lighting tube 1 there is an elongated carrier 5 provided with LEDs 7. The housing 3 has a translucent wall 3B, which has a structure such that the light shining through it resembles light emitted by a neon lamp. This effect is achieved by reflecting and to a lesser extend refracting the light emitted by the LEDs 7 by differently oriented surfaces. These light-reflecting and light-refracting surfaces are formed by layering the wall 3B of the housing using 3D printing. The transition 8A between the layers and the side surfaces 8B of the layers form the light-reflecting and light-refracting surfaces. The shape of the side surfaces 8B of the layers can be influenced by varying the degree of heating of the material used in 3D printing.

Description

[0001] Method for manufacturing a lighting tube

[0002] DESCRIPTION:

[0003] Technical field of the invention

[0004] The invention relates to a method for manufacturing a lighting tube, in particular in the form of a letter or a number, comprising an elongated housing provided with a translucent wall part extending in the longitudinal direction of the housing, the translucent wall part is formed in layers using a 3D printer, whereby a first layer of the wall part is applied in the longitudinal direction of the wall part and then a subsequent layer is applied on top of a previously applied layer, whereby an LED lighting is installed in the housing. More specifically, the invention relates to a method for manufacturing a lighting tube in the form of a letter or a number or in the form of a number of letters and / or numbers and / or punctuation marks written together.

[0005] The method of 3D printing with the 3D printer can be any known 3D printing method such as fused deposition modeling and stereolithography.

[0006] Background of the invention

[0007] A method according to the preamble of claim 1 is known from KR20200002364A. In this known method, a translucent bottom is manufactured using CNC. The side walls are then printed layer by layer on the bottom, with the layers being applied directly above each other. Finally, a translucent top plate is manufactured using CNC and attached to the side wall.

[0008] Summary of the invention

[0009] An object of the invention is to provide a method for manufacturing a lighting tube of the type described in the opening paragraph, with which a lighting tube can be manufactured in an inexpensive manner, the light emitted of which resembles light emitted by a neon lamp. To this end, the method according to the invention is characterized in that during the application of each of the following layers of the wall part, seen in cross-section of the lighting tube, this next layer is partly applied on the previously applied layer and partly formed obliquely above the previously applied layer. This achieves an effect that the light does not essentially refract but mainly reflects on the outside of the layers, so that more scattering of the light takes place, which produces a desired optical effect. By manufacturing the lighting tube with 3D printing, any desired shape of the lighting tube can be obtained. Minimum quantities of a design are not required because no investments are required in molds. The layered structure creates transitions between the different layers that form light reflecting surfaces that reflect the light emitted by the LEDs, causing the neon light-like appearance. The first layer can be applied as a wide strip or as a forward and return track, where the tracks are applied against each other or at a distance from each other.

[0010] WO2019 / 115285A1 describes a lighting tube, parts of which are printed in an upright position. The layers of this known lighting tube are therefore located next to each other in the longitudinal direction of the lighting tube and not on top of each other. Here too, the layers are applied directly above each other, with one layer being completely present on top of a previously applied layer below it.

[0011] During layer-by-layer 3D printing, a translucent wall part with a round cross-section is preferably formed so that the light is radiated on all sides and the appearance of a neon lamp is even better matched. It is even more preferable to form the entire housing layer by layer by 3D printing, with the translucent wall part forming the entire housing.

[0012] Installing the LED lighting in the lighting tube is preferably done by arranging an elongated carrier provided with LEDs, over the entire length of the lighting tube in the housing, whereby the LEDs are spaced apart on the carrier.

[0013] An embodiment of the method according to the invention is characterized in that during 3D printing the material that is applied is heated in such a way that the layers acquire an oval-shaped cross-section during application and subsequent cooling. The cross-section of the layers can be varied by increasing or decreasing the temperature of the material to be applied, causing the material to flow more or less. An oval shape of the cross-section of the layers was found to have the best effect on light reflection to best simulate the neon light look.

[0014] Preferably, the further layers are arranged in such a way that the tracks of layers present in a lower part of the housing project outwards with respect to the track present below them and the tracks of layers present in an upper part of the housing project inwards.

[0015] Preferably, the further layers each comprise a forward track as well as a return track, the tracks being spaced apart.

[0016] A further embodiment of the method according to the invention is characterized in that during the application of the layers of the translucent wall part, two parallel translucent partition walls are also applied layer by layer in the housing by 3D printing, which partition walls have a height that is greater than a quarter of the diameter of the lighting tube, where the LED lighting is installed between the partition walls. By placing the LEDs between two walls that are present within the tube wall, the light emitted by the LEDs is reflected even more, so that the light emitted by the lighting tube even better simulates neon light. By giving the dividing walls a minimum height (at least a quarter of the diameter of the lighting tube, better still at least a third or at least half of the diameter), sufficient reflection of the light takes place through the dividing wall to have a positive effect on the light emission of the lighting tube.

[0017] Preferably, after printing the first layer, the two parallel partition walls are applied layer by layer by means of 3D printing, with one partition wall being formed by forward tracks and the other partition wall by returning tracks during 3D printing, after which the elongated carrier provided with LEDs is placed between the upright partition walls.

[0018] In order to simplify the production of the lighting tube, a further embodiment of the method according to the invention is characterized in that the housing is formed into two separate parts that are attached to each other after forming, wherein the first layer and the upright partition walls form part of one of the parts and some of the further layers are part of the other part.

[0019] Yet a further embodiment of the method according to the invention is characterized in that the housing is further provided with a non-translucent further wall part extending in the longitudinal direction of the housing, which comprises two parallel side walls as well as a bottom that connects the two side walls to each other, wherein the further wall part is also formed layer by layer using a 3D printer, whereby a first layer of the further wall part is applied in the longitudinal direction of the lighting tube and then a subsequent layer is applied on top of a previously applied layer, after which the LED lighting is fitted between the two side walls, and wherein the translucent wall part is attached to the further wall part in such a way that the space between the side walls is in open connection with the space within the translucent wall part. With the lighting tube manufactured in this way, the LED lighting only shines directly onto the wall of the translucent wall part for a small part and the majority of the emitted light shines indirectly, after reflection, through the wall of the translucent wall part, resulting in a different light effect.

[0020] Brief description of the drawings

[0021] The invention will be explained in more detail below on the basis of an exemplary embodiment of the method according to the invention shown in the drawings. In the drawings:

[0022] Figure 1 shows a cross-section of a first embodiment of the lighting tube manufactured using the method according to the invention;

[0023] Figure 2 shows an illustration of the reflection of light in the lighting tube;

[0024] Figure 3 shows a lighting tube according to the invention in the form of the characters "3D";

[0025] Figure 4 shows the lighting tube shown in figure 3, disassembled into parts;

[0026] Figure 5 shows a cross-section of a second embodiment of the lighting tube manufactured using the method according to the invention;

[0027] Figure 6 shows a cross-section of a third embodiment of the lighting tube manufactured with the method according to the invention; and

[0028] Figure 7 shows a cross-section of a fourth embodiment of the lighting tube which is manufactured using the method according to the invention.

[0029] Detailed description of the drawings

[0030] Figure 1 shows a first embodiment of a lighting tube manufactured using the method according to the invention, in cross-section. The lighting tube 1 has an elongated housing 3 with a round cross-section in which an elongated carrier 5 provided with LEDs 7 extends. This carrier is, for example, formed by a flexible band on which the LEDs 7 are spaced apart. The housing 3 has a translucent wall 3B. In this method, the previously mentioned translucent wall part is formed by the entire wall of the housing.

[0031] The wall 3B of the housing has a structure such that the light shining through it resembles light emitted by a neon lamp. This effect is achieved mainly by reflecting and to a lesser extend by refracting the light emitted by the LEDs 7 by differently oriented surfaces. These light-reflecting and to a lesser extend lightrefracting surfaces are formed by arranging the wall 3B of the housing in layers. The transition 8A between the layers and the side surfaces 8B of the layers form the lightreflecting and light-refracting surfaces. The shape of the side surfaces 8B of the layers can be influenced by varying the degree of heating of the material used in 3D printing. In this embodiment of the method, the material that is applied is heated in such a way that the layers 9 acquire an oval-shaped cross-section during application and subsequent cooling.

[0032] While the housing 3 is being formed, a first layer 9A is applied to a work plate using a 3D printer. This layer extends in the longitudinal direction of the housing 3 to be formed. A second layer 9B is then applied to this first layer 9A, which, seen in cross-section of the housing 3, is partly present on top of the first layer 9A and partly extends outside the first layer 9A. This second layer 9B is arranged in a forward track 10A and a return track 10B in such a way that, seen in cross-section, the forward track is applied to one half of the first layer 9A and the backward track is applied to the other half of the first layer 9 A. returning track 10B is installed. If desired, the first layer 9 A can also be formed from a forward and a return track, whereby the two tracks are then placed against each other.

[0033] Subsequently, further layers 9C-E are successively applied to the previous layers. The further layers 9C-E are also formed by a forward and return track 10A, 10B, which, viewed in cross-section, are spaced apart from each other. The forward track 10A of each further layer 9C-E is applied to the forward track of the layer present below it, and the return track 10B of the further layer 9C-E is applied to the return track of the layer present below it. The tracks of layers 9D present in a lower part of the housing project outwards with respect to the track present below and the tracks of layers 9E present in an upper part of the housing project inwards. Finally, an upper layer 9F is applied to the forward and return tracks of the layer 9E underneath.

[0034] In the housing 3 there are two parallel translucent partitions 11, between which the elongated carrier 5 provided with LEDs 7 extends. These partition walls 11 have also been applied layer by layer using 3D printing. During the printing of a first number of further layers 9D, the two parallel partition walls 11 are arranged layer by layer between the forward and return tracks of these layers by means of 3D printing. The elongated carrier 5 provided with LEDs 7 is also placed between the upright partition walls 11.

[0035] The housing 3 is preferably formed in two parts 3 A and 3B, which are glued together after fitting the band 5 provided with LEDs 7 in the housing. This happens as follows. A number of further layers 9C are successively applied to the second layer 9B and all layers of the upright partition walls 11 are also applied to the second layer 9B or to a further layer applied thereto. The remaining number of further layers 9D-E and the top layer 9F are formed separately by 3D printing. First, a first of the further layers 9D1 is formed on a plate and successively the other further layers 9D- E and the top layer 9F are applied thereto. The parts 3A and 3B of housing 3 thus formed are attached to each other. Before this happens, the band 5 provided with LEDs 7 is first placed - preferably by clamping - between the partition walls.

[0036] In Figure 1, the tracks 10A and 10B are shown as separate layers that are attached to each other. If the temperature of the material is sufficiently high during 3D printing, these tracks will merge into one whole, as shown in Figure 2. This figure also schematically shows the reflection of some light rays emitted by the LEDs in the lighting tube.

[0037] In figure 3 a lighting tube that is manufactured using the method according to the invention is shown for illustration purposes. This lighting tube has a shape of the characters “3D”. Figure 4 shows this lighting tube in its three separate parts.

[0038] Figure 5 shows a second embodiment of a lighting tube 21 in crosssection, which has been manufactured using the method according to the invention. All parts that are equal to or similar to those of the first embodiment described above are indicated with the same reference numbers. In this lighting tube 21, the first layer 9A is wider than in the first embodiment, which makes the lighting tube 21 easier to manufacture. Furthermore, five LEDs 7 are present on the carrier on either side of the carrier.

[0039] Figure 6 shows a third embodiment of a lighting tube 31, which is manufactured using the method according to the invention, in cross-section. All parts that are equal to or correspond to those of the first embodiment described above are again indicated with the same reference numbers. This lighting tube 31 is formed as one part, wherein the first layer 9A is arranged in two tracks that are spaced apart. The elongated carrier with LEDs can be placed between the two upright partition walls 11 after printing the housing 3. In this embodiment, the carrier is formed by a hollow or solid tube 6 in which the LEDs are located.

[0040] Figure 7 shows a fourth embodiment of a lighting tube 41, which is manufactured using the method according to the invention, in cross-section. All parts that are equal to or correspond to those of the first embodiment described above are again indicated with the same reference numbers. In this lighting tube 41, the housing 3 is further provided with a non-translucent further wall part 3C extending in the longitudinal direction of the housing. This further wall part 3C has two parallel side walls 12 and a bottom 13 that connects the two side walls 12 to each other. In this embodiment, the side walls 12 and the bottom 13 are made of a material that is not translucent. The material can be any color. In this embodiment a material with a black color is used. However, one or both side walls and / or the bottom can also be translucent and still available in any desired color.

[0041] The further wall part 3C is also formed layer by layer using a 3D printer, whereby a first layer 14 A is also applied in the longitudinal direction of the lighting tube 1 and then a subsequent layer 14B is applied on top of a previously applied layer. After forming both wall parts 3B and 3C, the LED lighting 6 is placed between the two side walls 12. The translucent wall part 3B is then attached to the further wall part 3C, whereby the space between the side walls 12 is in open connection with the space within the light-translucent wall part 3B. In this embodiment of the lighting tube 41, the LED lighting 6 shines for the most part indirectly, after reflection of the light, through the wall of the translucent wall part 3C, resulting in a different light effect.

[0042] Although the invention has been explained in the foregoing with reference to the drawings, it must be noted that the invention is by no means limited to the embodiment shown in the drawings. The invention also extends to all embodiments deviating from the embodiment shown in the drawings within the framework defined by the claims.

Claims

CLAIMS:

1. Method for manufacturing a lighting tube (1; 21; 31; 41), in particular in the form of a letter or number, comprising an elongated housing (3) provided with a translucent wall part extending in the longitudinal direction of the housing (3B), the translucent wall part is formed layer by layer using a 3D printer, whereby a first layer (9 A) of the wall part (3B) is applied in the longitudinal direction of the wall part (3B) and then each time a subsequent layer (9B-E) is applied on a previously applied layer, whereby an LED lighting (6; 7) is installed in the housing (3), characterized in that during the application of each of the following layers (9B-E) of the wall part (3B), seen in cross-section of the lighting tube, this next layer (9B-E) is partly applied to the previously applied layer and partly formed diagonally above the previously applied layer.

2. Method according to claim 1, characterized in that a translucent wall part (3B) with a round cross-section is formed during layer-by-layer 3D printing.

3. Method according to claim 1 or 2, characterized in that the entire housing (3) is formed layer by layer by 3D printing.

4. Method according to claim 1, 2 or 3, characterized, that the translucent wall part (3B) forms the complete housing.

5. Method according to any of the preceding claims, characterized in that installing the LED lighting in the lighting tube is realized by applying an elongated carrier (5) in the housing (3), the carrier being provided with LEDs (7) over the entire length of the lighting tube, with the LEDs (7) spaced apart on the carrier (5).

6. Method according to any one of the preceding claims, characterized in that during 3D printing the material that is applied is heated in such a way that the layers (9) acquire an oval-shaped cross-section during application and subsequent cooling.

7. Method according to any one of the preceding claims, characterized in that the further layers (9B-E) are applied in such a way that the layers (9D) present in a lower part of the housing project outwards with respect to the layers present underneath and the layers (9E) present in an upper part of the housing project inwards.

8. Method according to any one of the preceding claims, characterized in that the further layers (9B-E) each comprise a forward track (10A), as well as a return track (10B), with the tracks (10A, 10B) being applied at a distance from each other.

9. Method according to any one of the preceding claims, characterized in that during the application of the layers of the translucent wall part (3B), two parallel translucent partition walls (11) are also applied layer by layer in the housing (3) by 3D printing, wherein the LED lighting (7) is installed between the partition walls (11).

10. Method according to claim 8 and 9, characterized in that, after printing the first layer (9 A), the two parallel partition walls (11) are applied layer by layer by means of 3D printing wherein one partition wall is formed by forward tracks and the other partition wall by return tracks during 3D printing, after which the elongated carrier (5) provided with LEDs (7) is placed between the upright partition walls (11).

11. Method according to claim 9 or 10, characterized in that the housing (3) is formed in two separate parts (3A, 3B) which are attached to each other after forming, with the first layer (9 A) and the upright dividing walls (11) form part of one of the parts (3B) and some of the further layers (9B-E) form part of the other part (3A).

12. Method according to any of the preceding claims 1-8, characterized in that the housing (3) is further provided with a non-translucent further wall part (3C) extending in the longitudinal direction of the housing and comprising two parallel side walls (12) as well as a bottom (13) that connects the two side walls (12) to each other, whereby the further wall part (3C) is also formed layer by layer using a 3D printer, whereby a first layer (14A) of the further wall part (3C) is applied in the longitudinal direction of the lighting tube (1) and then a subsequent layer (14B) is applied on top of a previously applied layer, after which the LED lighting (6) is applied between the two side walls (12), the translucent wall part (3B) is attached to the further wall part (3C) in such a way that the space between the side walls (12) is in open connection with the space within the translucent wall part (3B).

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