ES2604161A1 - Procedure and device for the encapsulation of a strip of leds, as well as such strip of leds encapsulada (Machine-translation by Google Translate, not legally binding) - Google Patents

Abstract

Procedure for the encapsulation of a strip of leds, comprising as steps the guidance of the strip of leds to the entrance of a mold; the cold mixing of the components that make up a silicone to obtain said silicone; introduction of the silicone to the mold; coextrusion of the led strip with the silicone encapsulating it; and the introduction in a silicone curing oven. They are also objects of invention, a device for the same purpose, as well as, a flexible encapsulated led strip obtained by the above method and device. (Machine-translation by Google Translate, not legally binding)

Description

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PROCEDURE AND DEVICE FOR THE ENCAPSULATE OF A LED STRIP, AS WELL, SUCH LED STRIP ENCAPSULATED

DESCRIPTION

OBJECT OF THE INVENTION

The present invention is encompassed in the field of LED strip production, of which the linear lighting systems with LEDs. Specifically, it is related to a procedure and a device to carry out, by cold coextrusion, the encapsulation of the LED strips.

Likewise, it is also the object of the invention, a flexible strip of encapsulated LEDs obtained using the method and the device of the invention.

BACKGROUND OF THE INVENTION

Flexible LED strips with waterproof characteristics that allow it to be used both indoors and outdoors are known.

In the art, linear lighting systems such as flexible LED strips are usually named by their acronym "SILL", the same when they include a waterproofing coating and with optical functions are integrated optical systems that are named by their acronym in English "SOI."

Currently, the impermeability is achieved by the deposition of epoxies, polyurethanes or silicones on the flexible LED strip. The current waterproofing processes, for example, with silicone, are semi-automatic and consist of depositing the silicone on a section of LED strip of approximately 5 meters, which then must be replaced by a new section to carry out the deposition of the silicone in the new section of LED strip. Assuming a considerable increase in the manufacturing costs of the LED strip.

As an alternative solution to the previous one, PVC or silicone housings are usually used in which the LED strip is introduced to achieve its impermeability. Representing also high manufacturing costs of the LED strip.

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On the other hand, one of the main problems that LEDs have is the opening angle that it offers, which ranges between a minimum value of 120 ° and a maximum value of 140 °. With a view to increasing this angle, optics are often used. For this, normally, a profile is used, for example, of the "channel" type, usually of aluminum, PVC, etc., where the LED strip is embedded and fixed inside, and to which a top is incorporated lens that widens or decreases this angle, assuming a considerable increase in the manufacturing and installation costs of the LED strip.

For this reason, in a simple and economical way, it is necessary to design a flexible LED strip encapsulated with the built-in optics that is obtained in a continuous and automatic way, that of solution to the drawbacks of the known technique mentioned above.

DESCRIPTION OF THE INVENTION

The present invention is established and characterized in the independent claims, while the dependent claims describe other features thereof.

The object of the invention is a method and a device for encapsulating a LED strip, as well as said encapsulated LED strip that allows to reduce the manufacturing and installation costs of the LED strip. The technical problem to solve is to establish the stages of the procedure and the configuration of the device and the LED strip to reach the mentioned object.

The invention manages to effectively solve the technical problem posed, therefore, the particular conformation of the encapsulation of the LED strip by means of cold coextrusion of liquid silicone, allows the encapsulation to be carried out continuously and automatically, as well as, that said encapsulation can comprise the optics built-in Thus, it is possible to reduce, by approximately 60%, the costs of waterproofing the LED strip, that is, the incorporation of the encapsulation thereto; as well as, the addition of a profile, for example, of aluminum, and a lens to achieve the required illumination angle of the LEDs is eliminated. All of which results in a considerable reduction in the manufacturing and installation costs of the LED strip.

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In addition, the described procedure allows a continuous linear production, without interruption of the cadence, which makes the quality of the product obtained to a single standard more stable, unlike the non-continuous LED strips in which there are quality differences between them. .

With the expression "extended longitudinally" is meant to extend throughout the length of the LED strip.

With "cold" we mean a temperature close to room temperature. DESCRIPTION OF THE FIGURES

The present specification is complemented with a set of figures, illustrative of the preferred example, and never limiting the invention.

Figure 1A represents a schematic elevation view of the device for encapsulating a LED strip. Figure 1B represents a top view of the mold.

Figures 2 through 6 represent a front sectional view of embodiments of the LED strip encapsulated with the optics incorporated, obtained using the device of Figure 1.

Figures 7 to 11 represent a front sectional view of embodiments of fixing means applied to the encapsulated LED strip of Figure 2, but applicable to the embodiments of Figures 3 to 6.

Figure 12 depicts a front sectional view of an embodiment of heat dissipation means applied to the encapsulated LED strip of Figure 2, but applicable to the embodiments of Figures 3 to 6.

Figures 13 to 15 represent embodiments similar to those shown in Figures 2 to 6 in which the LED strip includes LEDs on both sides of its support, thus presenting encapsulated with the optics incorporated on both sides thereof. For clarity, the alpha angles, which are the same as for Figures 2 to 6, are not noted.

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Figures 18 and 19 represent the view of Figure 2 with projection on one side of the support and on both sides respectively.

Figure 20 represents a perspective view of a LED strip with the configuration of Figure 2 and with a projection.

Figures 21 and 22 represent the view of Figure 13 with projection on one side of the support and on both sides respectively.

Figure 23 represents a perspective view of the configuration of Figure 21.

Figure 24 represents a perspective view of the configuration of Figure 22. DETAILED EXHIBITION OF THE INVENTION

The present invention relates to a method and a device for encapsulating a LED strip (1), with a view to achieving impermeability characteristics in the LED strip for use both indoors and outdoors.

As shown in Figure 1, the device comprises a mold (2), which comprises a body (2.1) and a cover (2.2) so that a cavity (2.3) is created between them, which is shaped funnel

Preferably, the body (2.1) and the cover (2.2) are attachable with each other, the cover (2.2) being able to be fixed to the body (2.1) through any type of known fixing means (not shown in the figures), such as, screws - the most common -, pins, etc., that allow the coupling and disengagement of both pieces (2.1,2.2), as well as, maintain the appropriate dimensions of the cavity (2.3) while the cover (2.1) and the body (2.2) is coupled.

Likewise, the mold (2) comprises at least one inlet duct (2.4) of the LED strip (1) and at least one outlet duct (2.5) of the cavity (2.3) formed between its body (2.1) and its cover (2.2). Both ducts (2.4,2.5) are aligned or parallel, where, the inlet duct (2.4) can be arranged through the body (2.1), leading the LED strip (1) to the cavity (2.3), and the duct output (2.5), it is preferred that it is formed in the lid (2.2). For productivity, it is usual to have more

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of an inlet conduit (2.4) and the corresponding ones of exit (2.5), being habitual the use of two of entrance and two exit, optionally four but being able to be a greater number.

Preferably, the inlet duct (2.4), will have dimensions corresponding to the dimensions of the led strip (1) that passes through it, while the outlet duct (2.5), will comprise such dimensions and geometry that function as forming means (2.51) of the encapsulation of the LED strip (1), for example, in correspondence with the profile or perimeter contour of any of the embodiments shown in the figures from 2 to 17, forming in the encapsulation at least a protuberance with optical function, to change the angle of the emitted light, fixing ends, a heat dissipation surface, etc.

Thus, a plurality of caps (2.2) with different configurations of forming means (2.51) can be designed inside the outlet duct (2.5), which represent negatives of the perimeter profile that it is desired to give to the encapsulation of the LED strip (1), where, said covers (2.2) may be exchanged in the body (2.1) of the mold (2) as appropriate.

Additionally, water circulation pipes in the body (2.1), not shown in the figures, can be included for refrigeration that allows maintaining a low temperature even with the pressure to which the device is subjected.

For continuous feeding of the LED strip (1) to the mold (2), it is preferred that the device comprises a guide (4) of the LED strip (1) in the inlet duct (2.4) of the mold (2). The guide (4) comprises at least three aligning pulleys (4.1) arranged successively, which align and embed the LED strip (1) from a coil (5) where it is wound.

On the other hand, the body (2.1) of the mold (2) comprises an introduction duct (2.6), preferably lateral, where a mixture of liquid silicone with a cauterizing agent is introduced into the cavity (2.3).

Preferably, the mixing of the liquid silicone with its cauterizing agent is carried out mechanically and at the temperature of the components at room temperature, that is, cold, in a dense fluid mixer (not shown in the figures) to

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obtaining a homogeneous mixture of said components, which is introduced under pressure into the lateral duct (2.6) of the mold (2) by means of an endless thyme (6) of high torque, and subsequently introduced into the cavity (2.3 ).

The funnel-shaped cavity (2.3), crossed by the continuous advance of the LED strip (1), causes the silicone it contains to be deposited around said LED strip (1), achieving coextrusion of the LED strip LEDs (1) with the silicone encapsulating it, as it passes through the outlet duct (2.5). The encapsulation of the LED strip (1) will have a perimeter profile that corresponds to the dimensions and internal geometry of the outlet duct (2.5), that is, of the forming means (2.51).

Preferably, at the exit of the mold (2), the device comprises a longitudinal furnace (3) with traction by adhesive tape (3.1), whereby the adhesion thereof avoids the use of an additional drag, in which, carries out the curing of the silicone of the LED strip encapsulation (1). For example, in the oven (3), said curing could be carried out at a temperature of between about 150 ° C to 240 ° C, for a time of between about 60 seconds to 150 seconds.

In general, the temperature of the furnace (3) is defined according to the specifications of the mixture of the liquid silicone with its cauterizing agent or curing catalyst, while the length of said furnace (3) will depend on the time required for the complete curing of said mixture and the speed of the adhesive tape (3.1).

Conveniently, the adhesive tape (3.1) is responsible for the continued movement of the LED strip (1) through the device. In other words, the fixation of the LED strip (1) encapsulated on the adhesive tape (3.1) to the oven entrance (3), not only allows its transfer through the oven (3), but also constitutes the means of traction that allows the continuous movement of the LED strip (1) through the entire device, that is, from the unwinding of the coil (5) to its exit from the oven (3).

Optionally, the device also comprises a linear print head and a cutting head, not shown in the figures, to obtain the required length of the strip (1), or die cut (1,314) to obtain a shape, figures 20, 23 and 24.

In this way, the encapsulation of the LED strip (1) is carried out continuously, which results in a considerable saving of time and resources.

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Being then the procedure to encapsulate the LED strip (1), whose encapsulation is of a plastic material, initiated with the guidance of said LED strip (1) to the entrance of the mold (2).

In parallel, cold mixing is carried out at the temperature of the silicone components to obtain said silicone. Such components consist of liquid silicone and a cauterizing agent or catalyst for curing liquid silicone. The mixing of these components is produced by chemical reaction, which is regulated (accelerated / slowed down) with temperature. For this reason, for its convenient manipulation, it is required to keep the silicone obtained with said mixture at a low temperature, for example, at the initial temperature of its components.

Likewise, it is preferred that the production zone where the process is carried out is kept at low temperatures, because, once the mixing of the silicone components has been carried out, its curing will be accelerated before the temperature increase, with those temperatures being understood as nearby at room temperature, unlike known processes where plastics processing temperatures from 100 ° C are used.

Then, consecutively, an introduction of the silicone into the mold (2) and a coextrusion of the LED strip (1) with the silicone encapsulating it is performed. In both stages, a cold extrusion is performed, with a view to facilitating the manipulation of the silicone during them.

Preferably, in the coextrusion at least one protuberance with optical function is formed in the encapsulation of the LED strip (1) to change to the angle of the light emitted by the LEDs. Thus, there will be a LED strip (1) with the optics incorporated into its encapsulation. With which and in advantage of what is known in the state of the art, the addition of a profile and an external lens is eliminated to achieve the angle of illumination of the light emitted by the required LEDs.

Finally, the LED strip (1) encapsulated with the silicone is introduced in an oven (3) to carry out the curing of said silicone.

Optionally, after the curing stage in the oven an impression is carried out and subsequently a cut or die cut with a certain frequency in

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function of the furnace exit speed and the intended distance between cuts, to obtain the required length of the strip (1), or die cut (1,314), to obtain a form in the encapsulation, figures 20, 23 and 24.

At the end of the process, there is a flexible LED strip (1) encapsulated.

It is also the object of the present invention, a flexible strip of encapsulated LEDs (1), which, as shown in figures 2 through 17, comprises a laminar support (1.1), mainly a printed circuit, on which LEDs (1.2) are fixed on one of their faces, figures 2 to 12, 18 and 19, or on both sides, figures 13 to 17, 21 and 22, and an envelope (1.3) that completely surrounds the support (1.1) with the LEDs (1.2) as an encapsulation.

The envelope (1.3) has an upper outer face (1.31) that is facing the led (1.2), where said envelope (1.3) is made of flexible silicone. Preferably, of translucent liquid silicone.

Likewise, it is preferred that the upper outer face (1.31) of the envelope (1.3) comprises at least one protrusion with optical function.

For example, as in the embodiments of Figures 2 and 3, 13 and 14, the protuberance could be formed by at least one curved surface (1,311). Particularly, in the embodiment of Figures 2 and 13, the protuberance is formed by a curved surface (1,311) arranged concavely with respect to the LED (1.2), giving it a certain angle of illumination (a).

In the embodiment shown in figures 3 and 14, the protuberance is formed by three contiguous curved surfaces (1,311) forming a wavy profile where the central raven surface (1,311) is arranged convexly with respect to the led (1.2), giving it an angle of illumination (a) greater than that of the embodiment of Figure 2.

Similarly, the protuberance could be formed by a curved surface (1,311) connected to a straight surface (1,312). For example, the embodiments seen in Figures 4 and 5, 15 and 17.

In the case of the realization of figures 4 and 15, the protuberance is formed by an inclined straight surface (1,312) and a curved surface (1,311) arranged so

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Concave with respect to the led (1.2), orienting the angle of illumination (a) towards the side of the curved surface (1.311).

Figures 5 and 17 illustrate an embodiment of the LED strip (1) with two rows of LEDs (1.2), in this case, the protuberance is formed by two curved surfaces (1.311), one for each LED (1.2), joined by a straight surface (1,312) that separates them, where the curved surfaces (1,311) are arranged concave with respect to the corresponding led (1.2), giving each led (1.2), a certain lighting angle (a), as it happens in the embodiment of figure 2.

Likewise, as shown in Figures 6 and 16, the protuberance could be formed by an irregular surface (1,313) as a "saw wave", forming teeth whose straight sections are oriented towards the center of the LED strip (1), reducing the angle of illumination (a) of the led (1.2) with respect to the embodiment shown in figure 2, thereby adding a light diffusing effect.

The configurations mentioned above, when LEDs (1.2) are fixed on both sides of the laminar support (1.1), figures 13 to 17, at least one of the upper outer faces (1.31) may have a projection (1,310), figures 18 a 20 leds on one side, figures 21 to 24 leds on both sides, in a direction perpendicular to the laminar support (1.1), figures 18, 20, 21 and 23 for one side and figures 19, 22 and 24 on both sides. This projection (1,310) helps to fix the LED strip (1). Optionally, the projection (1,310) is regularly interrupted by cuts or dies (1,314), figures 20, 23 and 24. In projections 18 to 24 projections are represented only for the configurations of figures 2 and 13 by economy of figures, but they can also be implemented in the rest of the configurations, figures 3 to 12 and 14 to 17.

Optionally, when the LEDs (1.2) are arranged on only one of the faces of the laminar support (1.1), the envelope (1.3) also has a lower outer face (1.32) that is the opposite of the led (1.2), figures 7 a 12.

Additionally, as shown in figures 7 to 9, the lower outer face (1.32) of the envelope (1.3) could form a fixing end of the flexible LED strip (1), with recesses (1,321) and / or projections (1,322) extended longitudinally from the proximity of one or both of the sides (1.33) of the envelope (1.3).

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For example, in the embodiment of Figure 7, the fixing end of the LED strip (1) is formed by two opposite projections (1,322) arranged towards each side (1,33) of the envelope (1.3). For example, said projections (1,322) are suitable for running through a channel profile (not shown in the figures) of the location of the LED strip (1).

As for the embodiment of Figure 8, the fixing end of the LED strip (1) is formed by two incoming (1,321), which, for example, are suitable for running outside of an outgoing profile (not shown in the figures) of the location of the LED strip (1).

On the part of the embodiment shown in figure 9, the fixing end of the LED strip (1) is configured with a recess (1,321) and a projection (1,322) arranged on the respective sides (1,33) of the enclosure (1.3 ), which can also be used to crimp on a profile (not shown in the figures) of the location of the LED strip (1).

In other possible embodiments, seen in Figures 10 and 11, the fixing end of the flexible LED strip (1) could be formed between the upper outer face (1.31) and the lower outer face (1.32) of the envelope (1.3 ), for example, in the form of a circular protuberance (1,331), figure 10, or of opposite projections (1,332) (figure 11) extending longitudinally on at least one of the sides (1.33) of the envelope (1.3). Thus, for example, the LED strip (1) could be placed laterally in a gutter profile (not shown in the figures) with interior conformations where they fit the previously described (1,331, 1,332).

On the other hand, in an embodiment seen in Figure 12, the lower outer face (1.32) of the envelope (1.3) could form a heat dissipation surface of the flexible LED strip (1), with a plurality of fins ( 1,323), at least two, extended by the lower outer face (1,332).

Whenever technically possible, any combination of the previously described embodiments (figures 2 to 19, 21 and 22) could be formed in the envelope (1.3) of the LED strip (1), with a view to customizing said strip of LEDs (1) as required, either by providing it with one of the embodiments of extrusion with optical function (figures from 2 to 17), fixing end (figures from 7 to 11) and / or dissipation surface of heat (figure 12) of the LED strip (1), or any other possible not shown in the figures.

Additionally, coloring or printing means can be added on some of the parts of the envelope (1.3) in opaque, translucent or reflective colors to add other optical functionalities to the system.

In any of the aforementioned configurations, the envelope (1.3) may include printing with normal, reflective or laser ink, which serves to identify the product, batch, etc.

Claims (19)

5 10 fifteen twenty 25 30 35 1. -Procedure for the encapsulation of a strip of LEDs (1), being the encapsulation of a plastic material, characterized in that it comprises the following stages: to. guiding the LED strip (1) to the entrance of a mold (2); b. cold mixing of the components that form a silicone to obtain said silicone; C. introduction of silicone to the mold (2); d. coextrusion of the LED strip (1) with the silicone encapsulating said LED strip (1); and. introduction of the encapsulated LED strip (1) obtained in step d in an oven (3) for silicone curing. 2. Procedure according to claim 1, in which the coextrusion is formed at least one protuberance with optical function in the encapsulation of the LED strip (1) to change to the angle of the emitted light. 3. Procedure according to any one of claims 1 or 2 in which after the curing stage in the oven an impression is carried out and subsequently a cut or die cut (1.314) with a frequency determined as a function of the speed of exit from the oven and the intended distance between cuts or die cuts (1.314) in the package. 4. -Device for encapsulation of a strip of LEDs (1) with silicone comprising a mold (2), which comprises a body (2.1) and a cover (2.2) so that a cavity (2.3) is created between them ), the mold (2) has at least one inlet duct (2.4) of the LED strip (1) to said cavity (2.3) and at least one outlet duct (2.5) of said cavity (2.3), both being ducts (2.4,2.5) aligned or parallel, characterized in that said cavity (2.3) is funnel-shaped. 5. - Device according to claim 4, wherein the outlet duct (2.5) comprises forming means (2.51) of at least one protrusion with optical function in the encapsulation of the LED strip (1) to change to the angle of The emitted light. 6. Device according to claim 4, which further comprises a guide (4) of the LED strip (1) in the inlet duct (2.4) of the mold (2), the guide (4) comprises at least three alignment pulleys (4.1) arranged successively. 13 5 10 fifteen twenty 25 30 35 7. -Device according to claim 4, which further comprises a longitudinal oven (3) with traction by adhesive tape (3.1), for curing the silicone of the LED strip encapsulation (1). 8. Device according to claim 4 comprising a linear print head and a cutting or die cutting head. 9. - Flexible strip of encapsulated LEDs (1) comprising a laminar support (1.1) on which LEDs (1.2) are fixed on one of their faces or on both sides, and an envelope (1.3) that completely surrounds the support (1.1) with the LEDs (1.2) as an encapsulation, the envelope (1.3) has an upper outer face (1.31) that is the one facing the LED (1.2), characterized in that the envelope (1.3) is made of silicone. 10. -Tira according to claim 9, wherein the silicone is translucent. 11. -Tira according to claim 9, wherein the upper outer face (1.31) has at least one protuberance with optical function to change the angle of the emitted light. 12. -Tira according to claim 11, wherein the protuberance is at least one curved surface (1.311). 13. -Tira according to claim 11, wherein the protuberance is a curved surface (1,311) connected to a straight surface (1,312). 14. -Tira according to claim 11, wherein the protuberance is formed by an irregular surface (1313) forming teeth whose straight sections are oriented towards the center of the LED strip (1). 15. -Tira according to any of claims 9 to 14, wherein when LEDs (1.2) are fixed on one or both sides of the laminar support (1.1), at least one of the upper outer faces (1.31) has a projection (1,310 ) perpendicular to the laminar support (1.1). 16. -Take according to claim 15 wherein the projection (1,310) is regularly interrupted by cuts or dies (1,314). 14 17. -Tira according to any of claims 9 to 16 in which when the LEDs (1.2) are arranged on only one of the faces of the laminar support (1.1), the envelope (1.3) also has a lower outer face (1.32) which is the opposite of the led (1.2). 5 18. -Turning according to claim 17, wherein the lower outer face (1.32) of the envelope (1.3) forms a fixing end of the LED strip (1), with recesses (1,321) and / or projections (1,322) extended longitudinally. 10. 19.-Strip according to claim 17, wherein between the upper outer face (1.31) and the lower outer face (1.32) a fixing end of the LED strip (1) is formed, in the form of a circular protuberance ( 1,331) or opposite projections (1,332) extending longitudinally on at least one of the sides (1.33) of the envelope (1.3). 15. 20.-Strip according to claim 17, wherein the lower outer face (1.32) of the envelope (1.3) forms a heat dissipation surface of the flexible LED strip (1) comprising at least two fins (1,323) extended by the lower outer face (1,332). 21.-Strip according to any of claims 9 to 20 wherein the envelope (1.3) includes a print with normal, reflective or laser ink.