Patent Description:
The strips can be applied on profiles, tables, door and window frames, furnishing components in general, portions of walls, floors, ceilings and false ceilings, and in other various applications, internal or external, in which particular aesthetic and/or focused and/or distributed lighting effects are to be achieved.

Light strips are known which can be used in the field of lighting engineering and furnishing to create light points/zones distributed in specific portions of wall elements or furnishing components.

The development of LED and Oled (Organic LED) technology, together with increasingly advanced architectural requirements and proposals, has made it possible to develop technologically advanced solutions, enabling the creation of extremely sophisticated lighting effects, particularly in combination with profiles and edges of furnishing components, as well as doors and windows, partition walls, external walls and more.

A light strip of this type normally consists of a longitudinal support, with length prevailing over width, made of normally flexible material on which a thin single or double-layer copper coating is applied, which creates the conductive track or tracks for the electric power supply of the light sources.

This combination of flexible support and conductive coating forms a so-called PCB (Printed Circuit Board) on which the light sources are applied, as well as the corresponding electric/electronic power supply and management components, and from which the light sources derive their electric power.

In correspondence with the positioning of the light sources, a base made of rigid material is normally provided, which forms a stable support to correctly position and maintain in position the light sources, and ensures the necessary mechanical stability of the strip, as well as of the welds and electrical connections. Once the desired arrangement of the light sources has been obtained, the strip is coupled with a profile made of plastic material or silicone, and the whole thing is then embedded in a resin, or similar material, which seals and defines the final shape of the strip.

The resin, usually of silicone material, ensures a high electrical insulation, making the strip applicable also outside.

One problem found in known solutions is that the strip, once completed, has little capacity to flex and bend with respect to at least two planes in space, for example in order to form a three-dimensional light element, since the internal rigidity of the connections can cause the breakage and/or interruption of the electrical connections.

This constitutes a limit for the possible applications and installations of said strips since they are unable to satisfy the increasingly advanced requirements and needs of architects and interior designers.

Document <CIT> describes a light strip comprising a flexible printed circuit contained by a profile provided with a series of supports located in sequence with each other which accommodate one or more light sources. The supports are reciprocally distanced by interruptions and electrically connected by means of a plurality of fins positioned on only one side of the circuit.

The fins, since they are located only on one side of the circuit, allow a limited supply of electric current to the light sources and furthermore the light strip obtained is asymmetrical with respect to a longitudinal axis, hence its structural resistance and the possibility of it being curved in space are limited.

Document <CIT> describes a light strip provided with fins on both sides of the printed circuit.

However, in order to connect the fins to the printed circuit, welds and connections are necessary, which lead to complications in manufacturing the circuit. Furthermore, the structural strength of the light strip is limited, and the welds and connections can deteriorate over time, with the risk that the electrical connection may be interrupted. Moreover, this light strip is intended for a flat application, and is therefore not suitable for three-dimensional curvatures.

Document <CIT> describes another light strip in which the connection between the various supports or bases occurs at the center and not on both sides of the printed circuit. To ensure a certain flexibility of the light strip, the printed circuit is mechanically bent in the vicinity of the central connections.

This light strip, due to the single central connection, can be improved from a structural point of view, in terms of resistance to wear and the supply of current to the light sources. Furthermore, due to the bends, it is difficult to guarantee a constant distance between the bases.

Document <CIT> describes another light strip, asymmetrical with respect to a longitudinal axis, which therefore substantially has the same problems as highlighted for <CIT>.

Document <CIT> discloses a solid state lighting module and method of fabricating the same.

One purpose of the present invention is therefore to provide a light strip which increases the degree of flexibility and torsion compared with known solutions, allowing it to be bent on several planes with respect to space, with large degrees of freedom and without the risk of breakage, with solid welds, without the formation of cracks and interruptions, even only partial, in the electrical connections.

Another purpose of the present invention is to obtain a light strip which can be bent on at least two planes in which neither the correct optical emission of the light sources nor the continuity of the light and/or the correct maintenance of a regular and constant pitch between the light sources are compromised.

Another purpose of the present invention is to obtain a light strip which can be curved/bent both on a plane transverse to a base surface of the strip, and also on the containing plane of the base surface itself, allowing to obtain a plurality of three-dimensional shapes.

Another purpose of the present invention is to perfect a method for manufacturing said strips which is in any case fast and economical, at the same time guaranteeing that the advantages indicated above are achieved.

In accordance with the above purposes, a light strip according to the present invention comprises: a flexible printed circuit provided with a series of supports located in sequence in a longitudinal direction; one or more light sources positioned on such supports; a profile for containing the flexible printed circuit; and a cover.

The supports are reciprocally distanced by interruptions and electrically connected by means of a plurality of fins which are positioned at the side of the supports and of the interruptions.

According to the invention, the flexible printed circuit develops along a longitudinal axis of symmetry; furthermore, the fins extend on both sides of the circuit and are made in one piece with the supports. Moreover, the fins located on one side of the flexible printed circuit mirror the fins located on the opposite side.

In this way, a light strip is obtained that is symmetrical with respect to the longitudinal axis of symmetry, and which therefore has high structural strength and bends homogeneously in any direction whatsoever. In this light strip, an electrical connection on both sides of the circuit is substantially created, thus allowing to use a double track for the electrical connection of the bases, with a consequent greater input of current, keeping the thickness of the printed circuit unchanged. This allows to manufacture light strips that are longer in length and also more wear resistant than light strips known in the field.

The flexible printed circuit provides fins and supports made in one piece. Therefore, no soldering or connections between these components are required. The fins are also able to bear the supports on both sides, creating a light strip that is extremely resistant.

The fins connect the supports electrically and physically and allow, even in steps that follow the coupling with the containing profile and with the cover, to flex and bend the light strip on two or more planes in space, according to the specific shape to be taken for the specific application.

In this way, the light strip is perfectly adaptable and malleable in order to follow even the most particular and complex shapes and profiles, for example the edge of a curvilinear furnishing component, even if it is not regular, a profile of an internal or external wall, or whatever else is required by the specific application.

With these fins and supports separated by interruptions, the present light strip can be bent more than a traditional light strip, therefore with lower radii of curvature than the radii of curvature normally achievable with a traditional light strip, without the risk of compromising its integrity and correct operation.

According to another aspect of the invention, the fins are positioned on a plane which is substantially orthogonal or slightly inclined with respect to a plane on which the flexible printed circuit lies.

According to another aspect of the invention, the fins have the shape of an arc or suchlike.

According to another aspect of the invention, the interruptions are positioned at a constant pitch along the longitudinal extension of the flexible printed circuit.

According to another aspect of the invention, the fins are positioned at a constant pitch along the longitudinal extension of the flexible printed circuit.

According to another aspect of the invention, the profile comprises opposite lateral walls provided with a tooth which is configured to allow a mechanical coupling of the fins with the profile.

According to another aspect of the invention, the tooth comprises, at the upper part, an inclined plane which facilitates the insertion of the circuit in the support and, at the lower part, an abutment surface for the fins. The circuit can therefore be inserted in the profile substantially in a snap-in manner.

According to another aspect of the invention, the tooth extends on each of the lateral walls for the whole extension of the profile.

The invention also concerns a method for manufacturing a light strip, comprising the following steps:.

According to another aspect of the invention, the fins are bent toward the inside of the light strip, that is, toward the flexible printed circuit, in such a way that they are disposed on a plane substantially orthogonal or slightly inclined with respect to a plane on which the flexible printed circuit lies.

With reference to the attached drawings, see in particular figs. from <NUM> to <NUM>, a light strip <NUM> comprises: a flexible printed circuit <NUM> provided with a series of supports <NUM>; one or more light sources <NUM> positioned on the supports <NUM>; a profile <NUM> for containing the flexible printed circuit <NUM>; and a cover <NUM>. The flexible printed circuit <NUM> develops along a longitudinal axis of symmetry Y and fins <NUM> extend on both sides of the circuit <NUM> and are made in one piece with the supports <NUM>.

The supports <NUM> are reciprocally distanced by means of interruptions <NUM> and electrically connected by means of a plurality of fins <NUM> which are positioned at the side of the printed circuit <NUM>, substantially outside the transverse dimension of the supports <NUM>. The fins <NUM> are made in one piece with the supports <NUM>. Please see for example <FIG> and <FIG>. Ultimately, a single flexible printed circuit <NUM> is therefore provided, provided with the fins <NUM> and the supports <NUM>.

Preferably, the flexible printed circuit <NUM> is substantially flat, and the supports <NUM> and the fins <NUM> have the same thickness.

In <FIG>, <FIG>, in a lower part of the present light strip <NUM>, the profile <NUM> has been deliberately removed, so as to show the fins <NUM> more clearly. Naturally, the profile <NUM> extends for the entire length of the flexible printed circuit <NUM>, therefore there are no uncovered segments. Furthermore, in <FIG>, <FIG> the cover <NUM> has also been omitted.

At least some of the supports <NUM> - made of electrically conductive material or comprising at least one layer of electrically conductive material - have holes <NUM> configured to accommodate the contacts of a normal connector for the electric power supply. The holes <NUM> are distributed along the entire extension of the flexible printed circuit <NUM>, so that the light strip <NUM> can be cut to the desired length.

from <NUM> to <NUM> the light strip <NUM> is provided with a row of fins <NUM> on each side of the flexible printed circuit <NUM>, while <FIG> show a longitudinal section along the center line.

The fins <NUM> of a same row are positioned on a plane P1 which is substantially orthogonal to a plane P2 on which the flexible printed circuit <NUM> lies. Therefore, the light strip <NUM> can have a substantially U-shaped cross-sectional shape, as shown in <FIG> or <FIG>.

Alternatively, the fins <NUM> can be slightly inclined with respect to the direction orthogonal to the plane P2, as shown in <FIG>, <FIG>, therefore the light strip <NUM> can be substantially V-shaped or trapezoidal-shaped.

The fins <NUM> can be made with any conformation whatsoever; however, in order to give a symmetrical shape to the connection between two supports <NUM>, guaranteeing flexibility and resistance, they can have an arched shape, for example semicircular, semielliptical or suchlike, please see <FIG>, <FIG> <FIG>, <FIG>, <FIG> for example, or comprise a plurality of rectilinear segments, or a combination of rectilinear and curved segments, as shown in <FIG> for example.

The interruptions <NUM> are preferably positioned at a constant pitch Y1 along the longitudinal extension of the circuit <NUM>, therefore along the axis of symmetry Y, so that they are reciprocally equidistant, as in <FIG> for example.

The fins <NUM> are also positioned at a constant pitch Y2 along the extension of the circuit <NUM>, therefore along the axis of symmetry Y, so that they are reciprocally equidistant, as in <FIG>.

The fins <NUM> located on one side of the circuit <NUM> mirror the fins <NUM> located on the opposite side, please see the two fins 17a and 17b of <FIG> for example, thus guaranteeing a more uniform behavior of the light strip <NUM> during the bending operations.

In the variant of the present light strip <NUM> shown in <FIG>, inside the profile <NUM>, in particular on each of the opposite lateral walls <NUM>, there is provided a tooth <NUM> configured to allow a mechanical coupling of the fins <NUM> with the profile <NUM>. The tooth <NUM> substantially allows the snap-in insertion of the circuit <NUM> inside the profile <NUM>. The tooth <NUM> comprises, at the upper part, an inclined plane <NUM> which facilitates the insertion of the circuit <NUM> in the support <NUM> and, at the lower part, an abutment surface <NUM> for the fins <NUM>. The tooth <NUM> preferably extends on each of the lateral walls <NUM> for the entire extension of the profile <NUM>.

The mechanical coupling between the fins <NUM> and the profile <NUM> allows to improve the resin coating step to create the cover <NUM>, and also to possibly eliminate the adhesive on the lower surface. During the resin coating the tooth <NUM> in fact prevents any incoming air from lifting the circuit <NUM>, thus creating shadows in the final light strip <NUM>, therefore a photometric improvement in the light emission is also achieved.

The presence of the fins <NUM> distributed along the length of the circuit <NUM> gives the strip <NUM> the ability to twist and flex on several planes in space, thus allowing to mold the strip <NUM> in a three-dimensional direction on the basis of the specific applications. Please see <FIG>, for example.

Furthermore, the fins <NUM> allow to possibly maintain a fixed center-distance between the various supports <NUM>, without the need for work to be carried out on the strip <NUM>.

Thanks to its flexibility and resistance, the light strip <NUM> can be wound in a reel and unrolled and cut, if necessary, as a function of the uses for which it is intended.

The circuit <NUM> can be manufactured by means of any technology currently available.

A rigid support can possibly be added to the circuit <NUM> if required by the uses for which it is intended, for example as a support for optics that require particular strength. By way of example, figs. from <NUM> to <NUM> show light sources <NUM> provided with optics <NUM>.

The flexible printed circuit <NUM> comprises the supports <NUM> and the fins <NUM> in a single body. The circuit <NUM> can advantageously be printed on flat sheets in the form of a plurality of pre-cut portions, wherein each portion comprises a plurality of supports <NUM> connected by respective fins <NUM>. The pre-cut portions can be removed from the sheet simply and quickly, and be assembled one to the other at respective ends in order to obtain a circuit <NUM> of the desired length.

The light source <NUM> can consist of LEDs or OLEDs, or another type of comparable or similar source.

Other components can also be added to the support <NUM> in order to meet specific project requirements, for example regulators, converters, BCRs, capacitors, optics, resistors and any other electronic/electrical component whatsoever.

The profile <NUM> for containing the flexible printed circuit <NUM> is preferably made of soft material, for example thermoplastic material. The profile <NUM>, possibly provided with teeth <NUM>, can be obtained by means of extrusion or also other technologies, such as casting, molding or other.

The profile <NUM> can be advantageously wound in a reel <NUM> and be unrolled when the flexible printed circuit <NUM> is inserted therein.

The cover <NUM> is obtained by casting a liquid element inside the profile so as to cover the flexible printed circuit <NUM> and guarantee a high degree of protection. The resin can arrive, at the upper part, flush with the profile <NUM>. This resin ensures a high electrical insulation, making the strip suitable to also be applied outdoors.

The present invention also concerns a method for manufacturing the light strip <NUM>, comprising the following steps:.

In an initial situation, such as in <FIG>, the fins <NUM> can be substantially coplanar to the supports <NUM> of the circuit <NUM>.

The fins <NUM> are then bent toward the inside of the light strip <NUM>, that is, toward the flexible printed circuit <NUM>, so that they are disposed on a plane P1 that is orthogonal, as in <FIG>, or inclined, as in <FIG>, <FIG>, with respect to the plane P2 on which the circuit <NUM> lies.

Ultimately, the light strip <NUM> can be advantageously curved in a three-dimensional way, thanks to the presence of the fins <NUM> which connect the supports <NUM> separated by suitable interruptions <NUM>.

In a "standard" flat circuit currently on the market, it would not be possible to obtain a three-dimensional curvature of the circuit itself because this would be damaged if curved on an unsuitable plane. Furthermore, in traditional circuits there is a need for external elements such as cables, supports, connectors, or for complex work that uses equipment or machines that are very precise from a mechanical point of view, in order to obtain a uniform pitch between the elements being worked.

In manufacturing the strip <NUM> the equipment or machines are much simpler, since the flexible printed circuit <NUM> can be applied to the profile <NUM> manually or with a simple winder, as if it were an adhesive tape, and in any case either before or after insertion in suitable templates where the resin coating occurs.

The light strip <NUM> is also substantially free from rigid supports and therefore can be curved following even very small radii of curvature, without risking damage to the flexible printed circuit <NUM> or the resin. By means of the strip <NUM> it is therefore possible to create wide or narrow curvatures in a three-dimensional space, maintaining its integrity and efficiency.

Claim 1:
Light strip (<NUM>) comprising: a flexible printed circuit (<NUM>) contained by a profile (<NUM>), provided with a series of supports (<NUM>) located in sequence with respect to each other which accommodate one or more light sources (<NUM>) and a cover (<NUM>), said supports (<NUM>) are reciprocally distanced by means of interruptions (<NUM>) and electrically connected by means of a plurality of fins (<NUM>) positioned at the side of said circuit (<NUM>), in which said flexible printed circuit (<NUM>) develops along a longitudinal axis of symmetry (Y), in which said fins (<NUM>) extend on both sides of said circuit (<NUM>) and are made in one piece with said supports (<NUM>), and in which the fins (<NUM>) located on one side of said circuit (<NUM>) mirror the fins (<NUM>) located on the opposite side of said circuit (<NUM>).